Diagnostic catheters, guide catheters, visualization devices and chord manipulation devices, and related kits and methods

ABSTRACT

Described herein are devices, methods and kits for assessing and/or enhancing the accessibility of a subvalvular space of a heart, accessing the subvalvular space of the heart (e.g., to provide access for one or more other devices), and/or positioning one or more devices in the subvalvular space of the heart. The devices described herein may, for example, comprise catheters that may be used to manipulate one or more chordae tendineae, diagnostic catheters having different sizes and/or shapes (e.g., different curvatures), guide catheters having different sizes and/or shapes (e.g., different curvatures), and visualization catheters. In some variations, the devices, methods, and/or kits may be used to visualize a target site, such as a subannular groove of a heart valve. In certain variations, the devices, methods, and/or kits may be used to manipulate chordae tendineae to provide additional space in a ventricle of a heart (e.g., enhancing the accessibility of the ventricle).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/868,290, filed on Sep. 28, 2015, which is a continuation of U.S.patent application Ser. No. 13/619,331, filed on Sep. 14, 2012, nowissued as U.S. Pat. No. 9,173,646, which is a continuation of U.S.patent application Ser. No. 12/690,109, filed on Jan. 19, 2010, nowabandoned, which claims the benefit of U.S. Provisional Application No.61/145,964, filed on Jan. 20, 2009, U.S. Provisional Application No.61/160,230, filed on Mar. 13, 2009, U.S. Provisional Application No.61/160,670, filed on Mar. 16, 2009, U.S. Provisional Application No.61/178,910, filed on May 15, 2009, and U.S. Provisional Application No.61/178,938, filed on May 15, 2009, the disclosures of all of which areincorporated herein by reference in their entirety.

TECHNICAL FIELD

The devices, methods, and kits described herein related generally toheart valve repair and/or replacement procedures, such as mitral valverepair procedures. More specifically, the devices, methods, and kitsdescribed herein relate to assessing the accessibility of a subvalvularspace of a heart (e.g., using one or more diagnostic methods and/ordevices), enhancing the accessibility of a subvalvular space of a heart(e.g., using a chordae tendineae manipulation device), assessing theplacement and positioning of one or more devices in a subvalvular spaceof a heart (e.g., using one or more visualization methods and/ordevices), and/or providing one or more instruments with access to asubvalvular space of a heart.

BACKGROUND

Blood returning to the heart from the peripheral circulation and thelungs generally flows into the atrial chambers of the heart and then tothe ventricular chambers, which pump the blood back out of the heart.During ventricular contraction, the atrio-ventricular valves between theatria and ventricles (i.e., the tricuspid and mitral valves) close toprevent backflow or regurgitation of blood from the ventricles back tothe atria. The closure of these valves, along with the aortic andpulmonary valves, maintains the uni-directional flow of blood throughthe cardiovascular system. Disease of the valvular apparatus can resultin valve dysfunction, in which some fraction of the ventricular bloodregurgitates back into the atrial chambers.

Traditional treatment of heart valve stenosis or regurgitation, such asmitral or tricuspid regurgitation, involves an open-heart surgicalprocedure to replace or repair the valve. Current accepted treatments ofthe mitral and tricuspid valves include: valvuloplasty, in which theaffected leaflets are remodeled to perform normally; repair of thechordae tendineae (also referred to herein as “chords”) and/or papillarymuscle attachments; and surgical insertion of an “annuloplasty” ring,which involves suturing a flexible support ring over the annulus toconstrict the radial dimension. Other surgical techniques to treat heartvalve dysfunction include fastening (or stapling) the valve leaflets toeach other or to other regions of the valve annulus to improve valvefunction.

Additionally, advances have been made in the techniques and tools usedin minimally invasive heart surgery. For example, to avoid open heartprocedures (which may require that the patient's heart be stopped andthat the patient be put on a bypass machine), devices and methods havebeen developed for performing heart surgery via intravascular orpercutaneous access. Some challenges in performing these proceduresinclude positioning the treatment catheters or other devices at adesired location for performing the procedure, and deploying an implantor other treatment device at a desired location.

When the minimally invasive heart surgery to be performed is valverepair (e.g., mitral valve repair), part of the valve anatomy itself maybe used to overcome certain positioning challenges that may arise duringthe valve repair procedure. Specifically, the subannular space, such asthe subannular groove, which is described in further detail below, maybe used for catheter and device placement. See, e.g., U.S. patentapplication Ser. No. 10/461,043 (issued as U.S. Pat. No. 6,986,775);Ser. No. 10/656,797 (published as US 2005/0055087 A1); Ser. No.10/741,130 (published as US 2004/0193191 A1); Ser. No. 10/776,682(published as US 2005/0107810 A1); Ser. No. 10/792,681 (published as US2004/0243227 A1); Ser. No. 10/901,019 (published as US 2005/0065550 A1);Ser. No. 10/901,555 (published as US 2006/0058817 A1); Ser. No.10/901,554 (published as US 2005/0107812 A1); Ser. No. 10/901,455(published as US 2006/0025750 A1); and U.S. Ser. No. 10/901,444(published as US 2006/0025784 A1), all of which are incorporated hereinby reference in their entirety. As described in some of theseapplications, a catheter may be advanced to, and seated in, thesubannular groove and may be used to accurately position one or moredevices, tools, etc. (e.g., implants and/or other catheters) for valvetreatment. In this way, difficulty in accessing the valve annulus (e.g.,as a result of error in implant placement and/or entanglement withchordae tendineae, as discussed below) may be reduced.

As mentioned briefly above, the heart includes chordae tendineae, whichare tendons in the left and right ventricles, some of which connect theheart's papillary muscles to its mitral and tricuspid valves. Thesechords help to hold the mitral and tricuspid valve leaflets in position,preventing the valves from moving into the atria when the ventriclescontract. Primary or first-order chords attach papillary muscles to thefree edges of the valve leaflets, secondary or second-order chordsattach papillary muscles to the ventricular surfaces of the valveleaflets, and tertiary or third-order chords connect the ventricularwalls to the undersurfaces of the posterolateral leaflets. In somecases, the chords (especially the tertiary or third-order chords) maypresent obstacles to a heart valve repair procedure. As an example, theymay obstruct the advancement of a catheter within a subvalvular spaceduring a heart valve repair procedure (e.g., the catheter may becomeentangled in the chords).

In view of the above, it would be desirable, whether in a minimallyinvasive procedure or another type of procedure, to enhance thedeliverability of devices, implants, and/or tools to valvular tissueduring a heart valve repair procedure. For example, it would bedesirable to reduce the extent of interference presented by chordsduring a heart valve repair procedure. It would also be desirable toprovide additional devices, methods, and kits for visualizing one ormore regions of a heart (and/or implants within one or more regions of aheart). Furthermore, it would be desirable to provide devices, methods,and kits for assessing the accessibility of a heart region, and/or foraccessing a heart region.

BRIEF SUMMARY

Described here are devices, methods, and kits that involve assessing theaccessibility and/or geometry of a subvalvular space of a heart, such asa subannular groove region of the heart (e.g., beneath a mitral valve).For example, one or more diagnostic catheters and/or visualizationmethods and devices (e.g., visualization catheters) may be used in suchassessment. Additionally, devices, methods, and kits for accessing asubvalvular space of a heart are described here. An example of a devicethat may be used to access a subvalvular space of a heart is a guidecatheter. In some variations, a visualization method may be employed toensure accuracy in placing and positioning a guide catheter in thesubvalvular space. Moreover, devices, methods, and kits that may be usedto provide or enhance access to a subvalvular space of a heart (e.g., asubannular groove region of the heart) are described here. The accessmay be provided or enhanced by, for example, manipulating one or morechords to remove obstructions or obstacles presented by the chords. Asan example, certain devices, methods, and/or kits described here may beused to provide a catheter with access to a subvalvular space of a heartby cutting and/or otherwise manipulating one or more chords that mightinterfere with the placement and positioning of the catheter in thesubvalvular space. Cutting or otherwise manipulating one or more chordsmay make it easier to access a subvalvular space of a heart during aprocedure, such as a heart valve repair procedure, and to deliver one ormore tools (e.g., heart valve repair tools) to a target site. Suchenhanced delivery may result in decreased procedure time and/or reducedlikelihood of damage to cardiac tissue during the repair procedure,thereby benefiting the patient.

Some variations of methods described here may comprise visualizing asubvalvular space of a heart to assess its geometry and/oraccessibility. In certain variations, the methods may comprise advancinga catheter to a position proximate to the subannular groove anddelivering one or more radiopaque contrast agents into the subvalvularspace (e.g., through a port in a catheter). One example of a radiopaquecontrast agent is a solution of a compound containing iodine (e.g., adiatrizoate meglumine solution), although other appropriate radiopaquecontrast agents may alternatively or additionally be used. In certainvariations, the solution may be diluted, such as with saline (e.g., in a1:1 ratio). During and/or after delivery of the radiopaque contrastagent or agents, one or more distribution patterns of the radiopaquecontrast agent(s) may be viewed using X-ray fluoroscopy. Thesedistribution patterns may, for example, be used to determine and/oradjust the position of the catheter, as well as to view and identify thelocation and/or orientation of one or more implants in the subvalvularspace. In certain variations, a method may comprise circumnavigating thesubannular groove with the distal portion of a catheter to visualize thesubannular groove, the anatomy surrounding the subannular groove, and/orimplants positioned proximate to or at least partially in the subannulargroove.

Examples of implants that may be viewed under X-ray fluoroscopy includeanchors, which may or may not be coupled together (e.g., with a tether),and plication elements, such as local plication elements or staples. Insome variations, an implant may comprise one or more non-plicatingelements, such as one or more non-plicating anchors. Any portion of animplant may be radiopaque. For example, if an implant comprises two ormore anchors coupled together with a tether, at least a portion of thetether may be radiopaque. Moreover, more than one portion of an implantmay be radiopaque. For example, at least a portion of an anchor and/or atether of an implant may be radiopaque. Catheters or other devices mayalso include one or more radiopaque portions.

Also described here are methods for visualizing a region of a heartusing ultrasonic energy. In some variations of these methods, a distalportion of a catheter, such as a diagnostic catheter or guide catheter,may be advanced to a position proximate to, or at least partiallywithin, the subannular groove of a heart valve. The catheter maycomprise one or more ultrasonic transducers that may, for example, becoupled to the catheter body (e.g., disposed within a lumen in a distalportion of the catheter). The transducer or transducers may transmit andreceive ultrasonic energy, thereby allowing visualization of the anatomyproximate the transducer(s) and/or the catheter, and a determination ofthe relative positions of the anatomy and the catheter. Certainvariations of the methods may include rotating and/or translating thetransducer(s) substantially independently of the catheter.

In some variations, the methods may comprise determining and/oradjusting the position of a catheter based upon a location and/ororientation visualized using ultrasound. The location and/or orientationof one or more implants may also be determined using the methodsdescribed here. In certain variations, the methods may includecircumnavigating the subannular groove with a catheter comprising atransducer so that the subannular groove, the surrounding anatomy,and/or implants coupled to or near the subannular groove may bevisualized. In some variations, a method may comprise using bothultrasound to view the area in and around a heart valve region, andX-ray fluoroscopy to determine the location and/or orientation of aradiopaque implant or device, such as a catheter.

Other methods for verifying the position of a catheter in a heart valveregion are also provided. These methods may include, for example,advancing a first catheter comprising an ultrasonic transducer through asecond catheter (e.g., a guide catheter). The first catheter may beadvanced through the second catheter such that the transducer extendsbeyond a distal end of the second catheter. This may allow a regionaround the distal end of the second catheter to be visualized, so thatthe position of the second catheter relative to known anatomicstructures (e.g., the ventricular wall, papillary muscles, valveleaflets and/or chordae tendineae) may be ascertained or verified.

Some variations of the methods described here may also be used toposition a catheter proximate to or within the subannular groove. Somesuch variations may include using ultrasound to visualize theadvancement of a distal portion of a first catheter to a positionproximate to or at least partially within the subannular groove. Asecond catheter (e.g., a guide catheter) may then be advanced to aposition proximate to or at least partially within the subannular grooveby sliding the second catheter along the first catheter. In somevariations, these methods may include advancing a distal portion of thefirst catheter circumferentially along the subannular groove, advancinga distal portion of the second catheter through the first catheter to aposition within the subannular groove, and withdrawing the firstcatheter from the second catheter while leaving the second catheterpositioned in the subannular groove.

Devices for visualizing the subannular groove, the anatomy near thesubannular groove, and/or implants and/or devices in or near thesubannular groove are also described herein. In some variations, avisualization device may comprise a catheter comprising at least adistal portion and a proximal portion (e.g., coupled to the distalportion). The catheter may also comprise one or more (e.g., two, three,four, or five) ultrasonic transducers and/or scopes (e.g., rigid scopesor flexible scopes, such as fiber scopes).

In some variations in which a catheter comprises one or more ultrasonictransducers, the ultrasonic transducer(s) may, for example, be disposedin one or more window regions of the distal portion that are at leastpartially transparent to ultrasonic energy. In certain variations, awindow region may comprise a thin polymer film (e.g., having a thicknessof about 0.007 inch or less), and/or may extend over a substantialportion of a distal portion of a catheter. In some variations, acatheter may comprise a distal portion having an inner diameter of atleast about 0.035 inch (e.g., to accommodate rotation of a transducer).In certain variations, the catheter may further include a second lumen,in which at least one ultrasonic transducer may be disposed.

In some variations, a tensioning element may pass through a first lumenof the catheter and may be coupled to a distal portion of the catheter,thereby allowing the distal portion to be steered by applying tension tothe tensioning element. When the distal portion is flexed (e.g., to forma configuration of approximately maximum flexion), the catheter may havea cross-sectional diameter of, for example, about 1.0 inch to about 1.5inches (e.g., about 1.2 inches to about 1.4 inches, such as about 1.25inches). In some variations, the distal portion may be more flexiblethan the proximal portion. For example, a tensioning element may be usedto steer the distal portion without inducing substantial movement of theproximal portion. As an example, tension may be applied to thetensioning element to manipulate the distal portion without substantialmovement of the proximal portion. Enhanced flexibility of the distalportion may, for example, provide for good catheter maneuverabilitywithout compromising pushability.

In certain variations in which a catheter comprises one or more scopes,the scope(s) may, for example, be disposed in one or more lumens of thecatheter. In some variations, a catheter may comprise one or more scopehousings, such as a bubble-shaped housing. In some such variations, ascope may be partially disposed within a lumen of the catheter, and adistal portion of the scope may be positioned within the scope housing.The scope housing may be formed of one or more clear or transparentmaterials, so that the scope may be used to visualize the surroundingsof the scope housing. A device, such as a catheter, may comprise one ormore rotatable scopes, scope housings, and/or other components, and/ormay comprise one or more non-rotatable or fixed components.

In some variations, a catheter (e.g., a diagnostic catheter,visualization catheter, chord manipulation catheter, guide catheter,anchor deployment catheter, etc.) may be curved. This curvature may, forexample, enhance the catheter's stability and/or functionality, and/orits ability to access a target site. For example, a curved guidecatheter that provides access to a subannular groove of a mitral valvemay be used to help position a guidewire so that the guidewire at leastpartially (e.g., completely) encircles the subannular groove. In certainvariations, the guide catheter may position the guidewire such that theguidewire experiences little or no apparent interference with chordaetendineae and/or is level with the mitral valve in its distal portion.In some variations, a catheter (e.g., a diagnostic catheter,visualization catheter, chord manipulation catheter, guide catheter,anchor deployment catheter, etc.) may comprise a compound curve (i.e.,including at least two different curve regions, such as three, four, orfive curve regions). At least some of the curves of the compound curvemay define different planes. The different planes may, for example,correspond to different anatomical landmarks. In certain variations, acatheter may have one or more curves that correspond to anatomicalfeatures of a specific patient. In some variations, a catheter may bepre-shaped to engage or fit within a subannular groove of a heart.

Also described here are methods for accurately positioning one or morecatheters (e.g., diagnostic catheters, guide catheters, etc.) in asubvalvular space of a heart. For example, a method may comprisepositioning a guide catheter in a subvalvular space of a heart such thatthe guide catheter will be highly effective in orienting one or moreinterventional devices in the subvalvular space. This may, for example,result in relatively accurate deployment and positioning of implantsand/or other treatment devices in the subvalvular space. Additionally,the guide catheter may be positioned so that the likelihood of medicalcomplications arising from use of the guide catheter may be relativelysmall. Catheters (e.g., diagnostic catheters, guide catheters, etc.) maybe advanced to a target site and positioned at the target site using oneor more visualization methods described here. These methods may be usedto achieve highly accurate advancement and positioning of the catheters.The visualization methods may be used with the catheters described here,or may be used with other catheters, and vice-versa. Moreover, thevisualization methods described here may be used to advance and positionother types of devices, as appropriate.

In certain variations, a relatively small diagnostic catheter may beused to assess the accessibility and/or geometry of a subvalvular spaceof a heart. The diagnostic catheter may alternatively or additionally beused to gather information that, in turn, may be used to help predicttherapeutic device shapes or configurations suitable for specificpatient anatomies. The diagnostic catheter may, for example, be a 6 Frcatheter (i.e., having an outer diameter of 2 millimeters) or a 9 Frcatheter (i.e., having an outer diameter of 3 millimeters). Othersuitable sizes may also be used. In some cases, the diagnostic cathetermay indicate that a region would be inaccessible by a larger catheter,such as a larger guide catheter, unless modifications are made to theregion prior to advancement of the guide catheter therethrough. Forexample, the region may include chordae tendineae that prevent acatheter from being able to be advanced through the region.

In the event that the diagnostic catheter indicates that a region isaccessible for a larger catheter, or in the event that a previouslyinaccessible region is rendered accessible, then a larger guide catheter(e.g., a 14 Fr guide catheter—i.e., having an outer diameter of 4.67millimeters) may be advanced to the region. Of course, it should beunderstood that some methods may comprise advancing a guide catheter toa region without advancing a diagnostic catheter to the region first. Alarger guide catheter that has been advanced to a subvalvular space of aheart may be used, for example, to orient, direct, and/or providesupport for one or more interventional devices that are to be used inthe subvalvular space. For example, a curved guide catheter may berouted into a subvalvular space of a heart and used to provide an anchordeployment catheter with access to the subvalvular space. Once properlypositioned in the subvalvular space, the anchor deployment catheter maythen be used to deploy one or more anchors (e.g., multiple tetheredanchors) into tissue in the subvalvular space. The anchors may be used,for example, to repair the heart tissue (e.g., in the case of tetheredanchors, by having their tether tensioned to cinch the anchors togetherand compress or gather the tissue). In cases in which the smallerdiagnostic catheter indicates that the subvalvular space is accessibleby the larger guide catheter, the larger guide catheter may be advancedinto the subvalvular space immediately after such indication, or at alater time (e.g., at least about 1 day later, at least about 2 dayslater, at least about 3 days later, at least about 4 days later, atleast about 5 days later, at least about 1 week later, at least about 10days later, at least about 2 weeks later, at least about 1 month later,or at least about 2 months later). In some variations, one or morevisualization methods and/or devices (e.g., a visualization catheter)may be used to help advance the guide catheter into the subvalvularspace, and to properly position the guide catheter there.

Of course, it is contemplated that the various different devices (e.g.,diagnostic catheters, visualization catheters, chord manipulationdevices, guide catheters, etc.) described herein may be used separatelyfrom each other—i.e., use of one of the diagnostic catheters in aprocedure does not require use of one of the visualization catheters,chord manipulation devices, or guide catheters in the procedure.Similarly, use of one of the visualization catheters does not requireuse of one of the diagnostic catheters, chord manipulation devices, orguide catheters, and use of one of the guide catheters does not requireuse of one of the diagnostic catheters, chord manipulation devices, orvisualization catheters. Additionally, use of one of the chordmanipulation devices does not require use of one of the diagnosticcatheters, guide catheters, or visualization catheters. Moreover, use ofone of the visualization methods described here does not require use ofone of the catheters and/or other devices described here, andvice-versa.

Although catheters and other devices and methods are described here inthe context of heart repair, they may be used in any procedure for whichthey are appropriate. As an example, a diagnostic catheter may be usedto assess the accessibility of a target site prior to stenting thetarget site and/or prior to performing a percutaneous transluminalcoronary angioplasty (PTCA) at the target site. Moreover, avisualization method described here may be used anywhere in which itsuse is appropriate, and in some cases may be used to position a devicethat is not a catheter or an implant.

As discussed above, some variations of devices and methods may be usedto manipulate one or more chords in a heart ventricle. As an example, incertain variations, a method of accessing a subvalvular space of a heartmay comprise advancing a first device into the subvalvular space of theheart, assessing whether the first device will pass between at least onechorda tendinea (e.g., a plurality of chordae tendineae) and aventricular wall of the heart, and manipulating the chorda tendinea orchordae tendineae in response to an assessment that the first devicewill not pass between the chorda tendinea or chordae tendineae and theventricular wall of the heart. A chorda tendinea may be manipulated by,for example, cutting it, grasping it, and/or heating it. In somevariations, a plurality of chordae tendineae may be manipulated bygathering them.

The first device may comprise a catheter, and in certain variations, maycomprise at least one sensor. In some variations, the method may furthercomprise passing a second device, such as a catheter, into thesubvalvular space of the heart after manipulating the chorda tendinea orchordae tendineae. The subvalvular space may be located beneath a mitralvalve of the heart.

In certain variations, a method of accessing a subvalvular space of aheart may comprise advancing a first device into a ventricle of a heart,using the first device to gather at least two chordae tendineae togetherto provide additional space between the chordae tendineae and aventricular wall of the heart, and advancing a second device, such as acatheter, into the additional space. Gathering the chordae tendineaetogether may comprise advancing a catheter comprising a hook into theventricle and hooking the chordae tendineae with the hook. In certainvariations, the method may comprise hooking the chordae tendineae withthe hook in a first region of the ventricle, and advancing the hook inthe direction of a valve in the ventricle to gather the chordaetendineae together. In some variations, the ventricle may comprise aleft ventricle and the valve may comprise a mitral valve.

While devices and methods having specific configurations and featuresare described here, it should be understood that any features,components or characteristics that are described here with respect tospecific devices or methods may be applied to other devices or methods,as appropriate.

In some variations, one or more of the devices (e.g., catheters)described here may comprise at least one radiopaque structure ormarking. The radiopaque structure or marking may be used, for example,to help properly align the device, and/or one or more other devices,during use. As an example, in certain variations, a catheter maycomprise one or more radiopaque markings that may be used to helpidentify the catheter's position in the body of a subject using X-rayfluoroscopy. Contrast agent may be used to further identify thecatheter's position in the subject's body, as described in additionaldetail below. As another example, in some variations, a chordmanipulation device may comprise one or more radiopaque markings thatmay be used to identify the device's position in the heart (e.g., priorto deploying a cutter from the device). Such markings may, for example,help to limit the likelihood of damage to heart tissue (e.g., bynon-target deployment of a cutter).

Certain variations of methods described here may comprise securinganchors to heart valve tissue after assessing and/or enhancing theaccessibility of the heart valve tissue, and/or after accessing theheart valve tissue. As an example, in some variations, a method maycomprise securing anchors to heart valve tissue before, during, and/orafter cutting or otherwise manipulating one or more chords.

Devices described here may have any appropriate configuration and insome variations, may comprise a catheter configured for advancement intoa subvalvular space of a heart. The catheter may, for example, includean elongated member comprising a proximal end, a distal end, and a lumentherethrough. The elongated member may comprise a first curve regiondefining a first plane and a second curve region defining a secondplane. In certain variations, the first and second planes may be at afirst angle of about 30° to about 90° (e.g., about 30° to about 65°,such as about 40°; about 50° to about 80°, such as about 60°) relativeto each other. For example, the first and second planes may beapproximately orthogonal to each other. In some variations, theelongated member of the catheter may further comprise a third curveregion defining a third plane. In some such variations, the second andthird planes may, for example, be at a second angle of about 00 to about50° (e.g., about 1° to about 50°; about 5° to about 450, such as about200; about 150 to about 35°, such as about 25°; about 20° to about 45°,such as about 30°) relative to each other. The elongated member mayfurther comprise additional curve regions defining additional planes.The angle between two planes defined by any of the curve regions of anelongated member of a catheter may be, for example, from about 0° toabout 90°. For example, the angle may be from about 00 to about 50°,such as about 5° to about 45° (e.g., 20°), about 15° to about 350 (e.g.,25°), or about 20° to about 45° (e.g., 30°). In certain variations, theangle may be from about 15° to about 90°, such as about 15° to about45°, about 200 to about 650, about 30° to about 90°, about 50° to about800 (e.g., 60°), or about 30° to about 65° (e.g., 40°).

As used herein, values and ranges provided for an angle between twoplanes may refer to the smaller angle between the two planes. Forexample, if two planes intersect to define two 30° angles and two 150°angles, then the smaller angle would be one of the 30° angles.Alternatively or additionally, when a catheter comprises a first curveregion defining a first plane, a second curve region defining a secondplane, and a third curve region defining a third plane, values andranges provided herein for an angle between two of the planes may referto an angle located within a space defined by the three planes. Incertain variations, values and ranges provided herein for an anglebetween two of the planes may refer to an angle located outside of aspace defined by the three planes.

In a catheter comprising one or more curve regions, at least one of thecurve regions (e.g., a valve curve region) may form an arc having an arcdiameter that may be from about 0.75 inch to about 1.5 inches (e.g.,about 0.8 inch to about 1.3 inches, or about 0.8 inch to about 1.1inches, such as about 1 inch). Alternatively or additionally, the arcmay define a central angle that may be, for example, from about 60° toabout 270° (e.g., about 900 to about 270°, about 110° to about 270°,about 150° to about 250°, or about 2000 to about 250°, such as about229.5°); about 60° to about 1800 (e.g., about 60° to about 160°, about100° to about 160°, or about 130° to about 1600, such as about 153°);about 60° to about 120° (e.g., about 75° to about 120°, or about 100° toabout 120°, such as about 114.75°); about 60° to about 80° (e.g., about70° to about 80°, such as about 76.5°); or about 90° to about 120°(e.g., about 900 to about 100°, such as about 90°).

Some variations of catheters may comprise an elongated member comprisingat least one deflectable portion. The deflectable portion may, forexample, comprise at least two different polymers, such as two polymershaving different durometers from each other. In certain methods, thedeflectable portion may be deflected to, for example, help the catheterto be more easily navigated to a target site.

A catheter described here may have a size of, for example, 4 Fr to 16 Fr(e.g., 4 Fr to 14 Fr, 4 Fr to 10 Fr, 4 Fr to 9 Fr, or 5 Fr to 10 Fr). Inother words, the catheter may have an outer diameter of, for example,1.33 millimeters to 5.33 millimeters (e.g., 1.33 millimeters to 4.67millimeters, 1.33 millimeters to 3.33 millimeters, 1.33 millimeters to 3millimeters, or 1.67 millimeters to 3.33 millimeters). In somevariations, the size of a catheter may be at least partially determinedby the function of the catheter. For example, a diagnostic catheter maygenerally be of a smaller size than its corresponding guide catheter. Incertain variations, a catheter may be sized and/or shaped for couplingwith one or more other catheters.

Some variations of methods described here for accessing a subvalvularspace of a heart may comprise advancing a first catheter (e.g., adiagnostic catheter) to the subvalvular space of the heart, advancing afirst guidewire through a first lumen of the first catheter and into thesubvalvular space of the heart, and advancing the first guidewire aroundat least a portion of a subannular groove region in the subvalvularspace of the heart. In this way, the accessibility of the subannulargroove region by a second guidewire advanced through a second lumen of asecond catheter (e.g., a guide catheter) may be assessed. In somevariations, the method may comprise withdrawing the first catheter andfirst guidewire from the subvalvular space of the heart. In certainvariations, the method may comprise advancing the second catheter to thesubvalvular space of the heart after the first catheter and firstguidewire have been withdrawn from the subvalvular space of the heart.In some variations, the second guidewire may be advanced through thesecond lumen of the second catheter and around at least a portion of thesubannular groove region. In certain variations, an anchor deploymentcatheter may be advanced over the second guidewire, and/or one or moreanchors may be deployed from one or more anchor deployment cathetersinto the subannular groove region. In some variations, the method maycomprise advancing the second catheter to the subvalvular space of theheart at least about 1 day (e.g., at least about 2 days, at least about3 days, at least about 4 days, at least about 5 days, at least about 1week, at least about 10 days, at least about 2 weeks, at least about 1month, at least about 2 months) after the first catheter and firstguidewire have been withdrawn from the subvalvular space of the heart.Alternatively, the second catheter may be advanced to the subvalvularspace immediately after the first catheter and first guidewire have beenwithdrawn, or may even be advanced over the first catheter and/or firstguidewire.

In certain variations, the placement and/or positioning of the secondcatheter may be achieved using one or more of the visualization methodsdescribed here. For example, after the first catheter and firstguidewire have been withdrawn, a visualization catheter may be advancedinto the subvalvular space of the heart, and specifically into thesubannular groove region. Using the visualization catheter, the operatormay inject one or more radiopaque contrast agents into the heart. Thecontrast agent(s) may be viewed under X-ray fluoroscopy to properlyposition the second catheter in the subvalvular space of the heart. Incertain variations, the visualization catheter may be advanced throughthe second catheter to access the subvalvular space of the heart and tohelp with the positioning of the second catheter with respect to thesubvalvular space.

Catheters described here may be made from any suitable material orcombination of materials. A catheter may comprise the same material ormaterials along its length, or may comprise at least two portions (e.g.,a proximal portion and a distal portion) comprising different materials.In some variations, a catheter may comprise one or more polymers (e.g.,throughout the length of the catheter, in a distal and/or proximalportion of the catheter, etc.). Examples of polymers that may besuitable for use in a catheter include high-density polyethylene (HDPE),low density polyethylene (LDPE), polypropylene, polytetrafluoroethylene(e.g., TEFLON™ polymer), polyamides (e.g., nylon), polyurethanes,ethylene vinyl acetate copolymers, polyethers, polyether block amidepolymers (e.g., polyether-block co-polyamide polymers, such as PEBAX®polyether block amide copolymer, including but not limited to PEBAX® 35Dpolymer, PEBAX® 40D polymer, PEBAX® 55D polymer, PEBAX® 63D polymer, andPEBAX® 72D polymer), silicone rubber, and copolymers, blends, andcomposites thereof.

In some variations, a catheter may comprise a combination of two or moredifferent polymers. As an example, a portion of a catheter (e.g., adistal portion) may comprise PEBAX® 72D polymer and PEBAX® 35D polymer.In certain variations in which a catheter comprises two or moredifferent polymers, the catheter may comprise discrete polymericsections (at least two of which comprise different polymers). Thediscrete polymeric sections may, for example, be formed by coextrudingthe polymers so that they are adjacent each other, or by individuallyforming each polymeric section and then coupling them to each other(e.g., using heat fusing methods). In certain variations, a catheter maycomprise multiple polymers that are combined with each other (e.g., in amixture). In some variations, a catheter may comprise at least twoportions comprising polymers having different durometers. For example, acatheter may comprise one portion comprising a first PEBAX® polymer, andanother portion comprising a second PEBAX® polymer having a differentdurometer from the first PEBAX® polymer.

As described above, some catheters may comprise proximal and distalportions having different flexibilities. For example, a catheter maycomprise a distal portion that is more flexible than a proximal portionof the catheter. This may, for example, cause the catheter to exhibitgood pushability, while also exhibiting good maneuverability. In somevariations, the proximal portion of a catheter may be reinforced (e.g.,with a braided or woven mesh, or with a metal) to provide it withrelative stiffness or hardness (e.g., which may enhance the pushabilityof the catheter). Also, as discussed above, some catheters may be atleast partially radiopaque. For example, a catheter may comprise one ormore radiopaque materials (e.g., in a wall portion of the catheter). Asan example, certain variations of catheters may comprise a polymercomposite comprising one or more radiopaque materials, such as bariumsulfate (BaSO₄) or bismuth trioxide (Bi₂O₃), and/or may comprise one ormore radiopaque markers (e.g., formed by one or more metals).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is an illustrative depiction of a cross-sectional view of aheart, and

FIG. 1B is another illustrative depiction of a cross-sectional view ofthe heart of FIG. 1A, with a variation of a guide catheter advancedthrough the aorta into the left ventricle.

FIG. 2A is a flowchart representation of a variation of a method forassessing the accessibility of a subvalvular space of a heart, and FIG.2B is a flowchart representation of a variation of a method fordeploying anchors into a subvalvular space of a heart.

FIGS. 3A-3K schematically depict a variation of a method for deliveringmultiple tissue anchors into a subvalvular space of a heart.

FIG. 4 is a cross-sectional depiction a variation of a catheter that maybe used to visualize a region of a heart.

FIG. 5 is an illustrative depiction of a pathway within a heart for acatheter to access a mitral valve region of the heart.

FIG. 6A is an illustrative top view of a subject on an operating table;FIG. 6B is an illustrative view of the subject of FIG. 6A, taken alongline 6B-6B; and FIG. 6C is an illustrative side view of the subject ofFIG. 6A under a variation of a C-arm X-ray fluoroscope.

FIG. 6D is an illustrative depiction of a short-axis view of asubvalvular space of a heart, looking up at the mitral valve, and FIG.6E is the short-axis view of FIG. 6D, with a variation of a catheteradvanced into the subvalvular space of the heart, and used to injectcontrast agent into the subvalvular space.

FIG. 6F is an illustrative depiction of a long-axis view of asubvalvular space of a heart, and FIG. 6G is the long-axis view of FIG.6F, with a variation of a catheter advanced into the subvalvular spaceof the heart, and used to inject contrast agent into the subvalvularspace.

FIGS. 7A-7C depict a variation of a method for visualizing a subannulargroove region of a heart using contrast agent.

FIG. 8A is a fluoroscopic image (short-axis view) of a subvalvular spaceof a heart after contrast agent has been injected into it; FIG. 8B isanother fluoroscopic image (short-axis view) of a subvalvular space of aheart after contrast agent has been injected into it; FIG. 8C is afluoroscopic image (short-axis view) of a guide catheter positioned in asubannular groove of a heart, with an accompanying injection of contrastagent; and FIG. 8D is a fluoroscopic image (short-axis view) of acatheter and implant in a subvalvular space of a heart.

FIG. 8E is a fluoroscopic image (long-axis view) of a subvalvular spacein an ovine heart showing placement of a catheter in the subvalvularspace, and FIG. 8F is a fluoroscopic image (short-axis view) of asubvalvular space in an ovine heart showing placement of a guidewire anda catheter in the subvalvular space.

FIG. 9 is a side view of a variation of a catheter that may be used todeliver contrast agent to a target site in a heart.

FIG. 10 depicts a variation of a method for visualizing a subannulargroove of a heart (and the surrounding area) using ultrasound.

FIGS. 11A and 11B illustrate a variation of a method for accessing asubannular groove of a heart using ultrasound.

FIG. 12 is a cross-sectional depiction of a variation of a catheter thatmay be used to visualize a region of a heart.

FIGS. 13A-13C depict different variations of catheters comprisingtensioning elements for steering.

FIG. 14 depicts another variation of a catheter that may be used tovisualize a region of a heart.

FIG. 15 shows an additional variation of a catheter that may be used tovisualize a region of a heart.

FIG. 16A is a side perspective view of a variation of a guide catheter;FIG. 16B is a cross-sectional view of the guide catheter of FIG. 16A,taken along line 16B-16B; FIG. 16C is an enlarged view of region 16C ofFIG. 16A; and FIG. 16D is a perspective view of a portion of the guidecatheter of FIG. 16A.

FIG. 16E is a perspective view of a variation of a diagnostic catheter.

FIGS. 17A and 17B are perspective views of another variation of adiagnostic catheter, FIG. 17C is a side view of the diagnostic catheterof FIGS. 17A and 17B after the diagnostic catheter has been rotated;FIG. 17D is a cross-sectional view of the diagnostic catheter as shownin FIG. 17C, taken along line 17D-17D; FIG. 17E is a view of thediagnostic catheter as shown in FIG. 17C, taken along line 17E-17E; FIG.17F is a view of the diagnostic catheter as shown in FIG. 17E, takenalong line 17F-17F; and FIG. 17G is a view of the diagnostic catheter asshown in FIG. 17F, taken along line 17G-17G.

FIGS. 18A and 18B illustrate flexed and extended configurations,respectively, of a variation of a catheter.

FIG. 19A is a perspective view of an additional variation of adiagnostic catheter.

FIG. 19B is an illustrative view of the advancement of a variation of adiagnostic catheter into a subvalvular space of a heart.

FIG. 20 is an illustrative depiction of a variation of a diagnosticcatheter and three planes defined by three different regions of thediagnostic catheter.

FIG. 21A is an illustrative depiction of another variation of adiagnostic catheter and two planes defined by two different regions ofthe diagnostic catheter, FIG. 21B is another illustrative depiction ofthe diagnostic catheter of FIG. 21A and two planes defined by twodifferent regions of the diagnostic catheter; and FIG. 21C is anadditional illustrative depiction of the diagnostic catheter of FIG. 21Aand two planes defined by two different regions of the diagnosticcatheter.

FIG. 22A is an illustrative depiction of an additional variation of adiagnostic catheter, showing the radius of curvature of a first regionof the diagnostic catheter that defines a first plane; FIG. 22B is anillustrative depiction of the diagnostic catheter of FIG. 22A, showingthe radius of curvature of a second region of the diagnostic catheterthat defines a second plane; and FIG. 22C is an illustrative depictionof the diagnostic catheter of FIG. 22A, showing the radius of curvatureof a third region of the diagnostic catheter that defines a third plane.

FIGS. 23A-23K are perspective views of different variations ofdiagnostic catheters having different shapes.

FIG. 24A is a perspective view of a variation of a fixture for shaping acatheter, FIG. 24B is an exploded view of the fixture of FIG. 24A; FIG.24C depicts the positioning of a catheter on the fixture of FIGS. 24Aand 24B, where the fixture will be used to shape the catheter; FIG. 24Dis an exploded view of another variation of a fixture for shaping acatheter, and FIGS. 24E-24G are illustrative views of additionalvariations of fixtures for shaping a catheter.

FIGS. 25A-25D are cross-sectional views of a portion of a heart,schematically illustrating a variation of a method for deploying ananchor into a region of a mitral valve annulus of the heart.

FIGS. 26A-26C are schematic cross-sectional views of a variation of aself-forming anchor attaching to body tissue, and FIGS. 26D-26F arecross-sectional views of variations of anchors attaching to body tissue.

FIGS. 27A-27F schematically demonstrate a variation of a method forapplying anchors from the subvalvular space of a heart.

FIG. 28 shows a transseptal approach to a left ventricle of a heart.

FIG. 29 shows a transapical approach to a left ventricle of a heart.

FIG. 30A is a perspective view of a variation of a diagnostic catheter,FIG. 30B is a side view of the diagnostic catheter of FIG. 30A after thediagnostic catheter has been rotated; FIG. 30C is a cross-sectional viewof the diagnostic catheter as shown in FIG. 30B, taken along line30C-30C; FIG. 30D is a view of the diagnostic catheter as shown in FIG.30B, taken along line 30D-30D; FIG. 30E is a view of the diagnosticcatheter as shown in FIG. 30D, taken along line 30E-30E; FIG. 30F is aview of the diagnostic catheter as shown in FIG. 30E, taken along line30F-30F; and FIG. 30G is a view of the diagnostic catheter as shown inFIG. 30F, taken along line 30G-30G.

FIG. 31A is a perspective view of a variation of a diagnostic catheter,FIG. 31B is a side view of the diagnostic catheter of FIG. 31A after thediagnostic catheter has been rotated; FIG. 31C is a cross-sectional viewof the diagnostic catheter as shown in FIG. 31B, taken along line31C-31C; FIG. 31D is a view of the diagnostic catheter as shown in FIG.31B, taken along line 31D-31D; FIG. 31E is a view of the diagnosticcatheter as shown in FIG. 31D, taken along line 31E-31E; FIG. 31F is aview of the diagnostic catheter as shown in FIG. 31E, taken along line31F-31F; and FIG. 31G is a view of the diagnostic catheter as shown inFIG. 31F, taken along line 31G-31G.

FIG. 32A is a perspective view of a variation of a diagnostic catheter,FIG. 32B is a side view of the diagnostic catheter of FIG. 32A after thediagnostic catheter has been rotated; FIG. 32C is a cross-sectional viewof the diagnostic catheter as shown in FIG. 32B, taken along line32C-32C; FIG. 32D is a view of the diagnostic catheter as shown in FIG.32B, taken along line 32D-32D; FIG. 32E is a view of the diagnosticcatheter as shown in FIG. 32D, taken along line 32E-32E; FIG. 32F is aview of the diagnostic catheter as shown in FIG. 32E, taken along line32F-32F; and FIG. 32G is a view of the diagnostic catheter as shown inFIG. 32F, taken along line 32G-32G.

FIG. 33A is a perspective view of a variation of a diagnostic catheter,FIG. 33B is a side view of the diagnostic catheter of FIG. 33A after thediagnostic catheter has been rotated; FIG. 33C is a cross-sectional viewof the diagnostic catheter as shown in FIG. 33B, taken along line33C-33C; FIG. 33D is a view of the diagnostic catheter as shown in FIG.33B, taken along line 33D-33D; FIG. 33E is a view of the diagnosticcatheter as shown in FIG. 33D, taken along line 33E-33E; FIG. 33F is aview of the diagnostic catheter as shown in FIG. 33E, taken along line33F-33F; and FIG. 33G is a view of the diagnostic catheter as shown inFIG. 33F, taken along line 33G-33G.

FIG. 34A is a perspective view of a variation of a diagnostic catheter,FIG. 34B is a side view of the diagnostic catheter of FIG. 34A after thediagnostic catheter has been rotated; FIG. 34C is a cross-sectional viewof the diagnostic catheter as shown in FIG. 34B, taken along line34C-34C; FIG. 34D is a view of the diagnostic catheter as shown in FIG.34B, taken along line 34D-34D; FIG. 34E is a view of the diagnosticcatheter as shown in FIG. 34D, taken along line 34E-34E; FIG. 34F is aview of the diagnostic catheter as shown in FIG. 34E, taken along line34F-34F; and FIG. 34G is a view of the diagnostic catheter as shown inFIG. 34F, taken along line 34G-34G.

FIG. 35A is a perspective view of a variation of a diagnostic catheter,FIG. 35B is a side view of the diagnostic catheter of FIG. 35A after thediagnostic catheter has been rotated; FIG. 35C is a cross-sectional viewof the diagnostic catheter as shown in FIG. 35B, taken along line35C-35C; FIG. 35D is a view of the diagnostic catheter as shown in FIG.35B, taken along line 35D-35D; FIG. 35E is a view of the diagnosticcatheter as shown in FIG. 35D, taken along line 35E-35E; FIG. 35F is aview of the diagnostic catheter as shown in FIG. 35E, taken along line35F-35F; and FIG. 35G is a view of the diagnostic catheter as shown inFIG. 35F, taken along line 35G-35G.

FIG. 36A is a perspective view of a variation of a diagnostic catheter,FIG. 36B is a side view of the diagnostic catheter of FIG. 36A after thediagnostic catheter has been rotated; FIG. 36C is a cross-sectional viewof the diagnostic catheter as shown in FIG. 36B, taken along line36C-36C; FIG. 36D is a view of the diagnostic catheter as shown in FIG.36B, taken along line 36D-36D; FIG. 36E is a view of the diagnosticcatheter as shown in FIG. 36D, taken along line 36E-36E; FIG. 36F is aview of the diagnostic catheter as shown in FIG. 36E, taken along line36F-36F; and FIG. 36G is a view of the diagnostic catheter as shown inFIG. 36F, taken along line 36G-36G.

FIG. 37A is a perspective view of a variation of a diagnostic catheter,FIG. 37B is a side view of the diagnostic catheter of FIG. 37A after thediagnostic catheter has been rotated; FIG. 37C is a cross-sectional viewof the diagnostic catheter as shown in FIG. 37B, taken along line37C-37C; FIG. 37D is a view of the diagnostic catheter as shown in FIG.37B, taken along line 37D-37D; FIG. 37E is a view of the diagnosticcatheter as shown in FIG. 37D, taken along line 37E-37E; FIG. 37F is aview of the diagnostic catheter as shown in FIG. 37E, taken along line37F-37F; and FIG. 37G is a view of the diagnostic catheter as shown inFIG. 37F, taken along line 37G-37G.

FIG. 38 is a schematic cross-sectional view of a variation of asteerable catheter with a pull wire.

FIGS. 39A and 39B are schematic side elevation and cross-sectionalviews, respectively, of the steerable catheter of FIG. 38 in a bentorientation.

FIG. 40A is a superior elevational view of a variation of a steerableguide catheter, FIG. 40B is a detailed superior elevational view of thedistal end of the guide catheter, FIG. 40C is a side elevational view ofthe distal end of the guide catheter; FIG. 40D is a detailed superiorelevational view of the proximal end of the guide catheter, and FIG. 40Eis a longitudinal cross-sectional view of the steering mechanism of theguide catheter.

FIG. 41A is a perspective view of a variation of a hemostatic seal; FIG.41B is a posterior elevational view of the seal; and FIG. 41C is across-sectional view of the seal.

FIG. 42 is a posterior elevational view of another variation of ahemostatic seal.

FIG. 43 is a superior elevational view of another variation of asteerable guide catheter.

FIGS. 44A-44C are schematic elevational views of a deformation region ofa catheter in various configurations.

FIGS. 45A-45D are schematic elevational views of other variousinterfaces between two sections of catheter body material.

FIGS. 46A-46C are schematic elevational views of various interfacesbetween two sections of catheter body material.

FIG. 47A is a schematic elevational view of a variation of a deformablezone of a catheter, and FIGS. 47B and 47C are various cross-sectionalviews of the deformable zone depicted in FIG. 47A.

FIG. 48A is a schematic elevational view of another variation of adeformable zone of a catheter, and FIGS. 48B and 48C are variouscross-sectional views of the deformable zone depicted in FIG. 48A.

FIG. 49A is a schematic elevational view of still another variation of adeformable zone of a catheter, and FIG. 49B is a cross-sectional view ofthe deformable zone depicted in FIG. 49A.

FIG. 50 is a side view in partial cross-section of a variation of avisualization device.

FIG. 51 is an illustrative side view of another variation of avisualization device.

FIG. 52 is a side view in partial cross-section of an additionalvariation of a visualization device.

FIGS. 53A-53D are front cross-sectional views of different variations ofvisualization devices.

FIG. 54A is a side view in partial cross-section of a variation of avisualization device, and FIG. 54B is a cross-sectional view of thevisualization device of FIG. 54A, taken at line 54B-54B.

FIG. 55 is a front cross-sectional view of a variation of avisualization device.

FIG. 56A is an illustrative side view in partial cross-section of avariation of a visualization device, and FIG. 56B is an illustrativeside view in partial cross-section of the visualization device of FIG.56A, disposed within a variation of a guide catheter.

FIG. 57 is an illustrative side view in partial cross-section of anothervariation of a visualization device.

FIGS. 58A-58C illustrate variations of a device and method for cuttingone or more chords, and FIG. 58D shows the device of FIGS. 58A-58Cpassing a chord without cutting the chord.

FIGS. 59A-59C illustrate additional variations of a device and methodfor cutting one or more chords, and FIGS. 59D-59F depict the device ofFIGS. 59A-59C being used with a different variation of a method forcutting one or more chords.

FIG. 60A is a side view of a variation of a device for cutting one ormore chords; FIG. 60B is a cross-sectional view of the device of FIG.60A, taken along line 60B-60B;

FIG. 60C depicts the cross-sectional view of FIG. 60B, after theposition of one of the components of the device has changed; and FIGS.60D-60J depict a variation of a method for cutting one or more chordsusing the device of FIGS. 60A-60C.

FIGS. 60K-60M show different variations of cutters that may be used indevices for cutting one or more chords.

FIGS. 60N and 60O depict additional variations of a device and methodfor cutting one or more chords.

FIG. 61 shows another variation of a device for cutting one or morechords.

FIGS. 62A-62E show variations of a device and method for cutting one ormore chords.

FIGS. 63A-63E show another variation of a device, and another variationof a method, for cutting one or more chords.

FIGS. 64A-64D depict additional variations of a device and method forcutting one or more chords.

FIGS. 65A-65E are illustrative depictions of further variations of adevice and method for cutting one or more chords.

FIGS. 66A-66C depict different variations of devices that may be used tocut one or more chords.

FIGS. 67A-67D are illustrative views of variations of a device andmethod for manipulating one or more chords.

DETAILED DESCRIPTION

Although a number of surgically implanted ventricular devices andprocedures, such as the implantation of an annuloplasty ring oredge-to-edge leaflet repair, are available for treating valvulardysfunction, each procedure presents its own set of risks to the patientor technical challenges to the physician. For example, the ability toaccurately and reliably position a cardiac implant during a beatingheart procedure, whether by open chest or minimally invasive access,remains elusive to the average practitioner. In particular, thepercutaneous or transvascular implantation of a ventricular devicedescribed herein poses a significant challenge due to the instabilityfrom the wall motion of a beating heart. Moreover, chords in asubvalvular space of a heart, such as tertiary or third-order chords,may present obstacles to the advancement and/or accurate positioning ofone or more heart valve repair tools in the subvalvular space.

The devices, methods and kits described here may generally be used toreshape atrio-ventricular valves or myocardium to improve hemodynamicperformance. In some variations, in order to allow such a reshapingprocess to take place, one or more chords in a subvalvular space of aheart may be cut and/or otherwise manipulated. This may, for example,provide additional space for the advancement of one or more tools thatmay be used to repair and/or assess the subvalvular space, such as oneor more of the diagnostic catheters, visualization catheters, and/orguide catheters described herein.

The implantation procedures described here are preferably transvascular,minimally invasive or other “less invasive” surgical procedures, but canalso be performed with open or limited access surgical procedures. Whenused for treatment of a cardiac valve dysfunction, the methods maygenerally involve assessing the accessibility of a target site in asubvalvular space of a heart using one or more diagnostic catheters. Ifthe target site is deemed accessible, or if the accessibility of thetarget site is improved (e.g., by removing one or more interferingchords), then the methods may also involve accessing the target siteusing a guide catheter, positioning one or more anchor deploymentdevices at the target site using a guide tunnel (also sometimes referredto as a tunnel catheter) advanced through a lumen of the guide catheter,deploying a plurality of slidably coupled anchors from the anchordeployment device(s), and drawing the anchors together to reduce theannular dimensions. More specifically, drawing the anchors togethertypically causes the tissue between the anchors to contract. This, inturn, may compress the annular tissue and cause separated valve leafletsto coapt, thereby reducing or ending valve regurgitation. In somevariations, self-securing anchors may be used—such self-securing anchorsmay have any of a number of different configurations, and may be usedwith other self-securing anchors, and/or with anchors that do notself-secure.

As discussed above, in some variations, a curved diagnostic catheterhaving essentially the same shape or a similar shape as a curved guidecatheter (but having a smaller cross-sectional profile than the curvedguide catheter) may be used to evaluate whether the guide catheter willbe able to access a subvalvular space of a heart. If the subvalvularspace is determined to be sufficiently accessible, then the proceduremay proceed as described above. In some cases in which the subvalvularspace is deemed inaccessible because of the presence of one or morechords, it may be rendered accessible by, for example, cutting thechord(s) that cause the inaccessibility.

Using a smaller diagnostic catheter to assess the accessibility and/orgeometry of the target site prior to advancement of a larger guidecatheter may make it less likely that the heart tissue will beinadvertently damaged by the guide catheter, or that the patient will besubjected to an unsuccessful procedure. For example, if a diagnosticcatheter indicates that a subvalvular space of a heart would not beaccessible by a guide catheter, then the patient would not be subjectedto having guide catheter advancement begin, only to experience the guidecatheter failing to reach the target site. A patient may also recovermore quickly after advancement of a smaller diagnostic catheter,relative to recovery after a failed attempt at advancing a larger guidecatheter.

It should be noted that certain variations of the methods described heremay not include assessing the accessibility of a target site with one ormore diagnostic catheters. For example, a method may include accessing atarget site with a guide catheter, without assessing the accessibilityof the target site with a diagnostic catheter first.

As discussed above, catheters, including one or more of the cathetersdescribed here, may include one or more curves. For example, adiagnostic catheter, visualization catheter, chord manipulationcatheter, guide catheter, and/or anchor deployment catheter may becurved. Generally, the curvature of a diagnostic catheter may beselected, for example, to optimize placement and positioning of thediagnostic catheter within a subvalvular space of a heart. Similarly,the curvature of a visualization catheter or guide catheter may also beselected to optimize placement and positioning of the visualizationcatheter or guide catheter within a subvalvular space of a heart.Likewise, the curvature of a chord manipulation catheter may be selectedto closely align with the geometry of a subvalvular space of a heart, sothat the chord manipulation catheter may provide relatively accurateanalysis of the subvalvular space. Additionally, the curvature of aguide catheter may be selected to facilitate the ability of a guidewireadvanced therethrough to navigate the subannular groove.

Also described herein are methods for visualizing a catheter and/or thearea surrounding a catheter during advancement of the catheter to atarget site and/or positioning of the catheter at the target site. Suchmethods may involve the use of, for example, X-ray fluoroscopy and/orultrasound (e.g., intravascular ultrasound, or IVUS). Some variations ofvisualization methods may employ echocardiography (e.g., intracardiacechocardiography). In some cases, rigid or flexible scopes, such asfiber scopes, may be used. The visualization methods may enablevisualization of, for example, one or more catheters or other devicesadvanced to the subannular groove, the anatomy of or around thesubannular groove, and/or implants delivered therein or thereto (e.g.,during a minimally invasive heart valve repair procedure). In certainvariations, one or more visualization methods and/or devices, such as avisualization catheter, may be used to help position a diagnosticcatheter, a chord manipulation catheter, a guide catheter, and/or one ormore other devices. This may result in enhanced positioning of thecatheters or other devices (e.g., thereby reducing error in implantplacement). It should be understood that while the methods and devicesdescribed herein focus on visualization of the subannular groove region,the methods and devices may be used to visualize any body region ofinterest, as appropriate.

As discussed above, also described here are devices, methods, and kitsfor manipulating one or more chords in a subvalvular space of a heart.For example, the chords may be severed and/or otherwise manipulated(e.g., pushed aside, gathered, etc.). Cutting or otherwise manipulatingchords in a heart may, for example, help to provide room for a catheter(e.g., a guide catheter) to be delivered to a subvalvular space of theheart. The chord manipulation devices may generally be configured to cutor otherwise manipulate one or more chords that may prevent cathetersand/or other tools from being used in the subvalvular space. As anexample, a device may comprise a cutting catheter configured to cutchords that obstruct advancement of a guide catheter to a target site,while leaving chords that provide sufficient space for passage of aguide catheter. In some variations, a cutting catheter may be used toprovide sufficient room for one or more anchor deployment devices sothat one or more anchors may be deployed into the cardiac tissue.

Catheters and Heart Valve Repair Procedures

Turning now to the figures, FIG. 1A shows a cross-sectional view of aheart (H) including an aorta (AO), a superior vena cava (SVC), a rightatrium (RA), a right ventricle (RV), a left atrium (LA), and a leftventricle (LV). As shown in FIG. 1A, a mitral valve (MV) comprisingmitral valve leaflets (MVL) separates left atrium (LA) from leftventricle (LV), while a tricuspid valve (TV) comprising tricuspid valveleaflets (TVL) separates right atrium (RA) from right ventricle (RV).There are two mitral valve leaflets (MVL), the anteromedial leaflet andthe posterolateral leaflet. In some cases, mitral valve leaflets (MVL)and/or tricuspid valve leaflets (TVL) may be referred to more generallyherein as leaflets (L). Heart (H) also includes papillary muscles in itsright ventricle (RVPM), as well as papillary muscles in its leftventricle (LVPM). Additionally, the mitral valve and the tricuspid valveeach comprise a valve annulus (not shown), discussed in further detailbelow.

FIG. 1A also shows a primary chorda tendinea (PCT), secondary chordatendinea (SCT), and tertiary chorda tendinea (TCT) in left ventricle(LV)—of course, these are only illustrative chords, and it should beunderstood that a heart typically has many of each of these differenttypes of chords.

As shown in FIG. 1A, right ventricle (RV) includes a subvalvular space(105), and left ventricle (LV) includes a subvalvular space (106). Thesubvalvular space, as used herein, generally includes the portion of theventricular chamber that is bound peripherally by the ventricular wall(VW), superiorly by the atrio-ventricular valve leaflets, and centrallyby the primary chordae tendineae (PCT), and is located along thecircumference of the valve annulus. The subannular groove region (104),as used herein, includes the space bordered by the inner surface of theventricular wall (VW), the inferior surface of valve leaflets (MVL) or(TVL), and the tertiary chordae tendineae (TCT) connected directly tothe ventricular wall (VW) and a leaflet (L). While FIG. 1A shows asubannular groove region (104) in left ventricle (LV), right ventricle(RV) also has a corresponding subannular groove region. Devices andmethods described here with respect to the subannular groove region inthe left ventricle may, of course, be used on the subannular grooveregion in the right ventricle, as appropriate.

FIG. 1B shows a cross-sectional depiction of heart (H) with onevariation of a guide catheter (100) advanced in a retrograde directionthrough aorta (AO) and into left ventricle (LV) (e.g., after beinginserted into the femoral artery). “Retrograde,” as used herein,generally refers to a direction opposite the expected flow of blood.This access route may be used to reach subvalvular space (106). Thedistal portion of the catheter may then be advanced, for example, underthe posterolateral mitral valve leaflet and into subannular grooveregion (104). Guide catheter (100) is generally a flexible elongatecatheter which may, for example, have one or more curves or bends towardits distal end to facilitate placement of the distal end (102) of theguide catheter at the desired location. Distal end (102) of guidecatheter (100) may be configured to be positioned at an opening intosubvalvular space (106) or within subvalvular space (106), such thatsubsequent delivery devices may be passed through guide catheter (100)into subvalvular space (106). Although the retrograde aortic accessroute preferably starts from a percutaneous or peripheral access site,in some variations, aortic access may be achieved by an incision in theascending aorta, descending aorta, aortic arch or iliac arteries,following surgical, thorascopic or laparoscopic access to a body cavity.

In certain variations, other spaces bound by or relating to one or morecardiac structures may be used as a target region of the heart. Thesestructures include but are not limited to the base of the ventricle, themitral valve, the tricuspid valve, the primary chordae tendineae, thesecondary chordae tendineae, the tertiary chordae tendineae, theanterior mitral valve leaflet chordae tendineae, the posterior mitralvalve leaflet chordae tendineae, the interleaflet chordae tendineae, thepapillary muscle, the anterior-lateral papillary muscle, theposterior-medial papillary muscle, the ventricular apical region, andthe ventricular apex. As an example, in some variations, a supra-apicalspace from about the base of the mitral valve leaflets to just above theventricular apex or apical region may be the target region. As anotherexample, in certain variations, the target region may be theperi-papillary muscle region, which includes the space about 1centimeter above and about 1 centimeter below the level of the papillarymuscle region, as well as the spaces between the papillary muscles. Insome variations, the target region may be the endocardial surfaceabutting or accessible from the given space or cardiac structures. Instill other variations, the target region may be a region locatedbetween the base and apex of a ventricle and between longitudinalborders drawn through the papillary muscles (e.g., either aposterior-lateral or an anterior-medial ventricular endocardialsurface). In other variations, the target region may exclude the spacealong the longitudinal axis from the base of a ventricle to the apex ofthe ventricle (e.g., the target region may be tubular or toroidal inconfiguration, with an internal border relating to a chorda tendinea).

FIG. 2A provides a flowchart depiction of a variation of a method (200)for assessing the accessibility of a target site within a region of aheart valve annulus. As shown there, this illustrative method comprisesloading a guidewire into a pigtail catheter (210). The guidewire may,for example, have a diameter of 0.035 inch (0.089 centimeter) and/or alength of 102.36 inch (260 centimeters), and/or the pigtail cathetermay, for example, be a 6 Fr pigtail catheter (i.e., having an outerdiameter of 2 millimeters). These examples are only intended to beillustrative, however, and other suitable guidewires and/or pigtailcatheters may be used. Moreover, in some variations, such as somevariations in which a relatively small diagnostic catheter (e.g., 6 Fr,or having an outer diameter of two millimeters) is used, a pigtailcatheter may not be used. For instance, a J-tip guidewire or a floppyangled tip may be sufficient to track within the vasculature and crossthe aortic valve.

Referring again to FIG. 2A, method (200) further includes loading thepigtail catheter into a diagnostic catheter (220). This may be achievedusing, for example, a peel-away introducer sheath (e.g., to temporarilystraighten the pigtail catheter during loading). Next, a sheath (e.g., a9 Fr sheath, or a sheath having an outer diameter of 3 millimeters) maybe advanced into a femoral artery, and a left coronary angiogram may beperformed in a lateral view (221). The fluoroscopic view may be adjustedto approximate the long axis of the left ventricle (i.e., to achieve along-axis view, described in further detail below). Thereafter, thediagnostic catheter (including the loaded pigtail catheter andguidewire) may be advanced into the sheath, over the aortic arch, andacross the aortic valve (222). The diagnostic catheter may be advancedinto and positioned within the body under fluoroscopic guidance, forexample, as discussed in further detail below.

After the diagnostic catheter has been advanced, the guidewire may bewithdrawn (224), and a ventriculogram may be performed through thepigtail catheter to find the short- and long-axis views (226). Ashort-axis view may be obtained, for example, by adjusting thefluoroscope to a projection of the face of the mitral valve (from theventricular side). In some variations, the short-axis view may beverified by such cues as a circular pattern of injected contrast agent,minimal exposure of the apical region in the projection, and possibleappearance of the papillary muscles. A long-axis view may be obtained,for example, by adjusting the fluoroscope to an edge-on or profileprojection of the mitral valve. This view may be verified by such cuesas a linear pattern of injected contrast agent, highlighting the valvewhich lies between the ventricle and the atrium. Short- and long-axisviews are discussed in additional detail below.

Next, the pigtail catheter may be withdrawn from the diagnostic catheter(228), and radiopaque contrast agent may be injected through thediagnostic catheter to visualize the subannular groove (230). In somevariations, the radiopaque contrast agent may be diluted (e.g., in a 1:1dilution). The method may then comprise urging the distal portion of thediagnostic catheter against the anterior or posterior wall in theshort-axis view (232). This may be achieved, for example, by carefullytorquing the diagnostic catheter. In some variations in which ananterior approach is used in a procedure on a mitral valve, it may bedesirable to place the distal tip of the diagnostic catheter directlybelow the anterior commissure of the mitral valve. Similarly, in certainvariations in which a posterior approach is used in a procedure on amitral valve, it may be desirable to place the distal tip of thediagnostic catheter directly below the posterior commissure of themitral valve.

In some variations, the position of the diagnostic catheter may beconfirmed by injecting small amounts of contrast agent through thediagnostic catheter. For example, alignment of the catheter with theedge of the pattern created by the injected contrast agent may indicatethat the catheter is accurately positioned at the target site. Incertain variations, the diagnostic catheter may be further manipulatedto achieve the desired positioning and stability of its distal portionagainst the anterior or posterior wall of the heart and behind thechordae tendineae in the subannular groove. The correct positioning ofthe diagnostic catheter may then be re-confirmed by injecting contrastagent through the diagnostic catheter. Typically, it is desired that thetip of the diagnostic catheter lie parallel to the mitral valve annulus(in the long-axis view) and apposed against the anterior or posteriorwall of the mitral valve annulus (in the short-axis view). Next, theguidewire (either the same guidewire or a new one) may be inserted intothe diagnostic catheter in the long- or short-axis view (234), and maybe advanced around the subannular groove (and behind the chordaetendineae) in both the long- and short-axis views (236). Finally, afterthe guidewire has circumnavigated the subannular groove, the correctpositioning of the guidewire may be verified by injecting contrast agentthrough the diagnostic catheter (238). If there is a significant amountof contrast agent between the endocardium and the guidewire (in theshort-axis view), then the guidewire may be repositioned and theverification step repeated, until the guidewire has been correctlypositioned.

In certain variations, method (200) may be repeated multiple (e.g., twoor three) times with the same subject. As an example, the method may berepeated using different diagnostic catheters having different sizesand/or different shapes.

It should be understood that method (200) may be modified according, forexample, to the preferences of the operator. As an example, the methodmay be modified so that it does not include loading a guidewire into apigtail catheter. As an alternative, the method may comprise providing apigtail catheter that has been preloaded with a guidewire. As anotherexample, in some variations (e.g., some variations in which a 6 Frdiagnostic catheter (having an outer diameter of 2 millimeters) isused), a pigtail catheter may not be used. As an additional example, themethod may not take place in the order shown in FIG. 2A. For example,the sheath may be advanced into the femoral artery and a left coronaryangiogram may be performed (221) prior to loading the guidewire into thepigtail catheter (210). As a further example, in some variations, eitherbefore or after urging the distal portion of the diagnostic catheteragainst the anterior wall (232), the diagnostic catheter may bepositioned as closely as possible to being level with the mitral valve.This positioning may be confirmed, for example, by injection of contrastagent viewed under X-ray fluoroscopy. As an additional example, in somevariations, instead of or in addition to inserting the guidewire intothe diagnostic catheter in the long-axis view (234), the guidewire maybe inserted into the diagnostic catheter using a different view (e.g., ashort-axis view). As another example, while a particular access routefor the diagnostic catheter has been described, any suitable accessroute may be used. Other alternative variations of method (200) may alsobe used, as appropriate.

FIG. 2B provides a flowchart depiction of one variation of a method(260) for deploying at least two anchors of an implant into a region ofa heart valve annulus. As shown there, this illustrative methodcomprises verifying the accessibility of a subannular groove region of aheart using a diagnostic catheter (270) (e.g., using method (200)described above with reference to FIG. 2A). Method (260) also comprisesadvancing a guide catheter to the subannular groove region (280),advancing a guidewire through a lumen of the guide catheter (284),advancing a guide tunnel over the guidewire (286), and proximallywithdrawing the guidewire from the guide tunnel (288). The guidecatheter may be advanced into and positioned within the body underfluoroscopic guidance, for example. In some variations, the guidecatheter may be placed and/or positioned at the target site using one ormore of the visualization methods and/or devices described below.Advancement of the guide catheter to the subannular groove region (280)may take place immediately after verifying the accessibility of thesubannular groove region using a diagnostic catheter (270).Alternatively, advancement of the guide catheter to the subannulargroove region may take place after a certain amount of time has elapsed(e.g., at least about 1 day, at least about 2 days, at least about 3days, at least about 4 days, at least about 5 days, at least about 1week, at least about 10 days, at least about 2 weeks, at least about 1month, at least about 2 months, etc.) from verifying the accessibilityof the subannular groove region using a diagnostic catheter.

In this particular variation, the guide tunnel comprises an outercatheter with a passageway in which an inner catheter slidably resides.However, other appropriate variations of guide tunnels may be used.Referring still to FIG. 2B, after the guidewire has been proximallywithdrawn, a first anchor deployment catheter may be advanced throughthe lumen of the guide tunnel (290) and a first anchor may be deployedfrom the first anchor deployment catheter, through an opening in theguide tunnel, and into a first region of the heart valve annular tissue(292). The first anchor is typically coupled or secured to a guideelement (or coupling member), such as a tether. In this way, after thefirst anchor is secured to heart tissue, the guide element will remaincoupled to the first anchor. The guide element may then be used as atrack or monorail for the advancement of one or more additional anchordeployment catheters thereover, and/or for the deployment of one or moreadditional anchors thereover. However, the guide element is also acomponent of the implant that interconnects the multiple anchors. Aportion of the guide element facilitates the cinching of the implant andremains in the body with the anchors after any anchor deploymentcatheters have been removed from the body.

While method (260) has been described above, other variations of methodsmay be employed, depending on the needs of the patient and operatorpreference. For example, in some variations, a guide catheter may beadvanced into the subannular groove region of a heart without firstverifying the accessibility of the subannular groove region using adiagnostic catheter. In certain variations, a method may comprisedeploying multiple anchors through a single opening in a guide tunnel(e.g., using the same anchor deployment catheter or different anchordeployment catheters). In some variations, a method may comprisesimultaneously deploying multiple anchors through multiple openings in aguide tunnel.

Guide elements may be made from any suitable or desirable biocompatiblematerial, and may be made of a single material or a combination ofmaterials (e.g., a guide element may be in the form of one long piece ofmaterial, or may comprise two or more pieces). Moreover, guide elementsmay be braided or not braided, woven or not woven, and/or reinforcedand/or impregnated with one or more additional materials. Asnon-limiting examples, a guide element may be made from (1) a suturematerial (e.g., absorbable suture materials such as polyglycolic acidand polydioxanone, natural fibers such as silk, and artificial fiberssuch as polypropylene, polyester, polyester impregnated withpolytetrafluoroethylene, nylon, etc.), (2) a suture-like material, (3) ametal (absorbable or non-absorbable), (4) a metal alloy (e.g., stainlesssteel), (5) a shape memory material, such as a shape memory alloy (e.g.,a nickel titanium alloy), (6) other biocompatible material, or (7) anycombination thereof. In some variations, a guide element may be in theform of a DACRON® polyester strip. In certain variations, a guideelement may comprise high-density polyethylene (HDPE), ultra-highmolecular weight polyethylene (UHMWPE), and/or polyetheretherketone(PEEK). Some variations of guide elements may have a braided textileconstruction. Certain variations of guide elements may be in the form ofa wire. Additionally, a guide element may include multiple layers,and/or may include one or more coatings. For example, a guide elementmay be in the form of a polymer-coated wire. In some variations, a guideelement may comprise a combination of one or more sutures and one ormore wires. As an example, a guide element may be formed of a suturethat is braided with a wire. Certain variations of guide elements may bein the form of monofilament or multifilament textile yarns or fibers. Insome variations, a guide element may be formed of one or more electrodematerials. In certain variations, a guide element may be formed of oneor more materials that provide for the telemetry of information (e.g.,regarding the condition of the target site).

Some variations of guide elements may include one or more therapeuticagents (e.g., drugs, such as time-release drugs). As an example, a guideelement may be partially or entirely coated with one or more therapeuticagents. In certain variations, a guide element may be used to deliverone or more growth factors and/or genetic regenerative factors. In somevariations, a guide element may be coated with one or more materials(e.g., a polymer) that encapsulate or control the release rate of one ormore therapeutic agents, and/or in which one or more therapeutic agentsare embedded. The therapeutic agents may be used, for example, to treata target site in which the guide element is disposed (and, in somecases, to which the guide element is fixedly attached or otherwisesecured). In certain variations, a guide element may include one or morelumens through which one or more therapeutic agents may be delivered.

After the first anchor has been deployed in the region of the heartvalve annular tissue, the first anchor deployment catheter may bewithdrawn proximally from the guide tunnel. While maintaining theexisting position of the outer catheter of the guide tunnel about thesubannular groove region, the inner catheter of the guide tunnel may berepositioned at a second opening of the outer catheter (294). A secondanchor deployment catheter may then be advanced over the guide elementthrough the lumen of the guide tunnel (296). While use of a secondanchor deployment catheter has been described, in some variations,subsequent deployment of anchors may be achieved by removing andreloading the first anchor deployment catheter. In other variations, thefirst anchor deployment catheter may be loaded with a plurality ofanchors and may not need to be withdrawn from the guide tunnel todeliver subsequent anchors.

During advancement of the second anchor deployment catheter over theguide element, the guide element may enter the second anchor deploymentcatheter through an opening at its distal end, and exit the secondanchor deployment catheter through an opening in its side wall that isproximal to its distal end. As an alternative, the guide element mayenter the second anchor deployment catheter through an opening at itsdistal end, and exit the second anchor deployment catheter through anopening at its proximal end, or at any other location proximal to thedistal end. As another alternative, the guide element may enter thesecond anchor deployment catheter through an opening at its distal end,exit the second anchor deployment catheter through an opening at itsdistal end, enter a side lumen of the second anchor deployment catheter,and exit the side lumen at a location proximal to its point of entryinto the side lumen. Other appropriate guide element routingconfigurations may also be used.

After the second anchor deployment catheter has been advanced over theguide element through the lumen of the guide tunnel, a second anchor maybe deployed into a second region of the heart valve annular tissue usinga second opening of the guide tunnel (298). While this variation of amethod includes deploying one anchor through one opening in a guidetunnel and then deploying another anchor through another opening in theguide tunnel, some variations of methods may alternatively oradditionally include deploying anchors in a different manner. As anexample, a method may include deploying multiple (i.e., at least two)anchors through a single opening in a guide tunnel. Two or more of theanchors may be deployed using the same anchor deployment catheter,and/or two or more of the anchors may be deployed using different anchordeployment catheters. As another example, a method may includesimultaneously deploying multiple anchors through multiple openings in aguide tunnel. Other suitable variations of methods may also be employed.

The procedure described above represents one variation of a method thatmay be used to treat the annular tissue of the mitral valve. In othervariations, other tissues or structures of the heart and vasculature mayalso be treated, including but not limited to the subvalvular apparatus,septal structures and the myocardium. In still other variations, one ormore cinchable implants may be deployed in non-cardiac tissues orstructures, for example, to treat gastrointestinal disorders such asobesity or genitourinary conditions such as incontinence, or to performcosmetic and reconstructive procedures.

FIGS. 3A-3K provide a more detailed depiction of the method shown inflowchart form in FIG. 2B, as well as a portion of the method shown inflowchart form in FIG. 2A. In FIGS. 3A-3K, the mitral valve (MV) isdepicted schematically from an inferior perspective looking in asuperior direction, but in other variations the tricuspid valve,pulmonary valve or aortic valve may be accessed. Referring to FIG. 3A, adiagnostic catheter (300) may be advanced into the subvalvular space(306) (FIG. 3B) of a heart, and more specifically into the subannulargroove region (304) of the heart. As shown in FIG. 3B, after diagnosticcatheter (300) has been positioned at the desired location in subannulargroove region (304), a guidewire (308) may be advanced through a lumenof diagnostic catheter (300) and at least partially routed aroundsubannular groove region (304). The diagnostic catheter may be used tohelp determine whether the anatomy of the subject (here, the subvalvularspace) is appropriate for passage of a guide catheter and routing of aguidewire therethrough. For example, here the diagnostic catheter may beused to help determine whether a guide catheter can be advanced to thesubvalvular space and a guidewire can be advanced through the guidecatheter and around all or a portion of the subannular groove region.Diagnostic catheter (300) may be, for example, from 5 Fr to 9 Fr in size(i.e., such that the diagnostic catheter has an outer diameter of 1.67millimeters to 3 millimeters). Specific, non-limiting examples ofdiagnostic catheter sizes that may be appropriate include 6 Fr (2millimeters outer diameter), 7 Fr (2.33 millimeters outer diameter), and9 Fr (3 millimeters outer diameter), although other appropriate sizesmay also be used.

If it is determined that the subject's anatomy will accept a guidecatheter and guidewire, then the guidewire and diagnostic catheter maybe withdrawn from the heart. Next, and as shown in FIG. 3C, a guidecatheter (340) may be advanced to subannular groove region (304) usingany of the access routes (or any other suitable access routes) describedherein. Guide catheter (340) may have a size of, for example, from 6 Frto 16 Fr (e.g., 14 Fr), or 2 millimeters outer diameter to 5.33millimeters outer diameter (e.g., 4.67 millimeters outer diameter).Other suitable sizes may also be used. Guide catheter (340) may alsohave an atraumatic tip. As shown in FIG. 3D, after guide catheter (340)has been positioned at the desired location in subannular groove region(304), a guidewire (344) may be advanced through the lumen of guidecatheter (340). Guidewire (344) may be advanced beyond the distal end(346) of guide catheter (340), so that guidewire (344) extends fartheralong subannular groove region (304) than guide catheter (340), as shownin FIG. 3D.

After guidewire (344) has been positioned in subannular groove region(304), a guide tunnel (348) may be advanced through guide catheter(340), over guidewire (344), as shown in FIG. 3E. As shown in FIG. 3E, adistal portion (342) of guidewire (344) extends from the distal end ofguide tunnel (348). Guide tunnel (348) may be any suitable catheter, andin some instances, it may be desirable that the guide tunnel bepre-shaped or pre-formed at its distal end, such as the guide tunnelillustrated in FIG. 3E. In certain variations, guide tunnel (348) mayhave a pre-shaped distal portion that is curved. In this way, the guidetunnel may more easily conform to the geometry of the atrio-ventricularvalve. Guide tunnels are described, for example, in U.S. patentapplication Ser. No. 12/366,553 (published as US 2009/0222083 A1), whichis incorporated herein by reference in its entirety.

It should also be understood that any of the catheters or guidewiresdescribed here may be pre-shaped or pre-formed to include any number ofsuitable curves, angles or configurations, and/or may be steerable. Insome variations, the radius of curvature of a curved distal section of acatheter may be generally larger than that of the subannular groove.When such a catheter is urged or situated against the subannular groove,the distal end of the catheter may naturally point outward against theannulus and ventricular wall. In other variations, the catheter may havea curved distal section having a radius of curvature that isapproximately the same as that of the subannular groove.

After guide tunnel (348) has been positioned in subannular groove region(304), guidewire (344) may be withdrawn proximally, as shown in FIG. 3F.An anchor deployment catheter (not shown) may then be advanced throughthe lumen of guide tunnel (348) and toward opening (354) at or adjacentto the distal tip (356) of guide tunnel (348). In the variation depictedin FIG. 3G, the anchor deployment catheter remains within guide tunnel(348), and an anchor (358) is deployed through opening (354) to attachto the body tissue. In other variations, however, the anchor deploymentcatheter may be extended through opening (354) of guide tunnel (348).

In some variations, opening (354) may be the distal-most anchordeployment opening of guide tunnel (348). In certain variations, one ormore openings may have a separate lumen in guide tunnel (348), so thatanchors deployed from such openings would not interfere with or restrictthe deployment of subsequent tissue anchors distal to those openings.Furthermore, although FIG. 3G depicts opening (354) as a side opening ofguide tunnel (348), in some variations, opening (354) may be located atdistal tip (356) and may be the same opening shown with a distallyprotruding guidewire (344) in FIG. 3E.

Anchor (358), shown in FIG. 3G, may be configured to self-expand as itexits the anchor deployment catheter and guide tunnel (348) toself-secure into the annular tissue accessible from subannular grooveregion (304). It should be understood that one or more anchors of animplant may be deployed into the annulus directly, while other anchorsmay be secured to other tissue in the vicinity of subannular grooveregion (304). For example, one or more anchors may be secured to thetissue below the annulus. Anchor deployment may be monitored, forexample, under fluoroscopy. After anchor (358) has been deployed, theanchor deployment catheter may be proximally withdrawn. A tether (360),attached to anchor (358) and seen best in FIGS. 3I and 3J, may then beused to facilitate the insertion of additional anchor deploymentcatheters toward the implantation site.

In this particular variation, as demonstrated in FIG. 3H, guide tunnel(348) is maintained in the same position while additional anchors (364)and (358′) are deployed from additional openings (364′) and (354′) alongguide tunnel (348). In some variations, one or more anchor deploymentcatheters may be serially inserted into guide tunnel (348) using tether(360) to serially guide anchors (364) and (358′) through openings (364′)and (354′). In certain variations, the anchor deployment catheters maybe loaded with one or more anchors at the point-of-use, while in othervariations the anchor deployment catheters may be pre-loaded at thepoint-of-manufacture. In some variations, the anchor deploymentcatheters may be reloaded at the point-of-use, while in othervariations, the anchor deployment catheters may be single-use devicesthat are discarded after anchor deployment. In certain variations, theanchor deployment catheters may be configured to hold two or moreanchors (358), (358′) and (364) and may be capable of deploying multipleanchors without requiring withdrawal of the anchor deployment catheterbetween anchor deployments. Still other multi-anchor deploymentcatheters may be configured to deploy multiple anchors simultaneouslythrough multiple openings of guide tunnel (348).

Anchors (358). (358′) and (364) may be deployed from the anchordeployment catheter and guide tunnel (348) in any suitable fashion,including but not limited to using a push-pull wire or a plunger, or anyother suitable actuation technique. Similarly, anchors (358), (358′) and(364) may be coupled to tether (360) by any suitable attachment method.For example, one or more knots, welded regions, and/or adhesives may beused. Alternate variations for anchor deployment and anchor attachmentsare described, for example, in U.S. patent application Ser. No.11/583,627 (published as US 2008/0172035 A1) and Ser. No. 12/505,332,filed on Jul. 17, 2009, both of which are incorporated herein byreference in their entirety. Additionally, anchor deployment methods,devices, and kits are described, for example, in U.S. patent applicationSer. No. 11/201,949 (published as US 2007/0055206 A1); U.S. patentapplication Ser. No. 12/366,553 (published as US 2009/0222083 A1); U.S.Provisional Application Ser. No. 61/160,230, filed on Mar. 13, 2009; andU.S. Provisional Application Ser. No. 61/178,910, filed on May 15, 2009,all of which are incorporated herein by reference in their entirety.

“Anchors,” for the purposes of this application, are defined to mean anyfasteners. Thus, the anchors may comprise C-shaped or semicircularhooks, curved hooks of other shapes, straight hooks, barbed hooks,single or multiple loop anchors, clips of any kind, T-tags, rivets,plication elements (e.g., local plication elements such as staples), orany other suitable fastener(s). In one variation, anchors may comprisetwo tips that curve in opposite directions upon deployment, forming twointersecting semi-circles, circles, ovals, helices or the like. In somevariations, the tips may be sharpened or beveled. In certain variations,the anchors may be self-forming. By “self-forming” it is meant that theanchors are biased to change from a first undeployed shape to a seconddeployed shape upon release of the anchors from a restraint. Suchself-forming anchors may change shape as they are released from ahousing or deployed from a lumen or opening to enter annular tissue, andsecure themselves to the tissue. Self-forming anchors may be made of anysuitable material or materials, such as spring stainless steel, orsuper-elastic or shape-memory materials such as nickel-titanium alloy(e.g., Nitinol).

In certain variations, anchors may be made of a non-shape-memorymaterial and may be loaded into an anchor deployment catheter in such away that they change shape upon release. For example, anchors that arenot self-forming may be secured to tissue via crimping, firing or otherapplication of mechanical force to facilitate tissue penetration and/orsecurement. Even self-securing anchors may be crimped in somevariations, to provide enhanced attachment to tissue. Other types ofmechanical force may alternatively or additionally be applied toself-forming anchors. In certain variations, anchors may comprise one ormore bioactive agents, including biodegradable metals and polymers. Insome variations, anchors may comprise electrode components. Suchelectrodes, may, for example, sense various parameters including but notlimited to impedance, temperature and electrical signals. In othervariations, such electrodes may be used to supply energy to tissue atablation or sub-ablation amounts.

In some variations, an implant may comprise multiple self-expanding,non-plicating anchors. In certain variations, an implant may comprisemultiple T-tag anchors. Some variations of anchors may comprise fibrousor porous materials in the shape of bars, rods, pledgets, or the like.In some cases, the fibrous or porous materials may expand in volume.Additionally, while the deployment of multiple anchors of the same shapeover a single guide element has been described, in certain variations, asingle guide element may be used to deploy multiple anchors havingdifferent shapes or non-uniform implantation sites. Similarly, in somevariations, a single guide element may be used in the deployment ofmultiple anchors having different sizes. Illustrative examples ofsuitable anchors are described in more detail, for example, in U.S.patent application Ser. No. 11/202,474 (published as US 2005/0273138A1), which is incorporated herein by reference in its entirety.

In the variations depicted in FIGS. 3A-3K, before a second anchordeployment catheter is advanced through guide tunnel (348), tether (360)is threaded into the second anchor deployment catheter and is slidablyengaged with a second anchor (364). In some variations, second anchor(364) may be preloaded into the second anchor deployment catheter beforethreading tether (360), while in other variations, the second anchor maybe pre-threaded before being loaded into the second anchor deploymentcatheter. Any of a number of different methods may be used to thread aguide element, such as tether (360), into an anchor deployment catheter,and to engage the guide element with an anchor. Other methods aredescribed, for example, in U.S. patent application Ser. No. 11/202,474(published as US 2005/0273138 A1), which is incorporated herein byreference in its entirety. Threading devices are described, for example,in U.S. patent application Ser. No. 11/232,190 (published as US2006/0190030 A1), which is also incorporated herein by reference in itsentirety.

With reference to FIG. 3J, after all of anchors (358), (358′) and (364)have been deployed into body tissue, guide tunnel (348) may be withdrawnfrom guide catheter (340). A termination catheter (374) may then beinserted through guide catheter (340) over tether (360). Terminationcatheter (374) may be used to facilitate tensioning of tether (360),thereby cinching anchors (358), (358′) and (364) together to remodel theannular tissue. The effect of this cinching on the valve geometry andblood flow may be viewed, for example, using ultrasound. Terminationcatheter (374) may also be used to secure the cinched anchors (358),(358′) and (364) with a termination member (376) that resists tetherloosening or slippage, as illustrated in FIG. 3K. In other variations,termination catheter (374) may secure tether (360) to an anchor or tobody tissue without the use of termination member (376). Devices andmethods for performing termination of cinchable implants are described,for example, in U.S. patent application Ser. No. 11/232,190 (publishedas US 2006/0190030 A1); Ser. No. 11/270,034 (published as US2006/0122633 A1); Ser. No. 12/576,955, filed on Oct. 9, 2009; and Ser.No. 12/577,044, filed on Oct. 9, 2009, all of which are incorporatedherein by reference in their entirety.

The catheters and other elongated members described herein, includingthe diagnostic catheters, guide catheters, guide tunnels, and anchordeployment catheters, may be formed of any of a number of differentmaterials. Moreover, at least two of the catheters that are used in aprocedure may be formed of the same material or materials, and/or atleast two of the catheters may comprise one or more different materials.In some variations, a method of treating heart valve tissue may compriseusing a diagnostic catheter and a guide catheter, where the diagnosticcatheter is essentially a scaled-down version of the guide catheter. Forexample, both of the catheters may be formed of the same material ormaterials, and may have the same shape. Alternatively, a method maycomprise using a diagnostic catheter and a guide catheter that differfrom each other in at least one aspect (in addition to having differentsizes). For example, the diagnostic catheter and guide catheter may havethe same shape, but may be formed of different materials. As an example,the diagnostic catheter may be formed of one or more materials that arestiffer than the material or materials used to form the guide catheter.

Non-limiting examples of suitable materials for the catheters describedhere include polymers, such as polyether-block co-polyamide polymers(e.g., PEBAX® polyether block amide copolymers, including but notlimited to PEBAX® 35D polymer, PEBAX® 40D polymer, PEBAX® 55D polymer,PEBAX® 63D polymer, and PEBAX® 72D polymer), copolyester elastomers,thermoset polymers, polyolefins (e.g., polypropylene or polyethylene,including high-density polyethylene (HDPE) and low-density polyethylene(LDPE)), polytetrafluoroethylene (e.g., TEFLON™ polymer) or otherfluorinated polymers, ethylene vinyl acetate copolymers, polyamides,polyimides, polyurethanes (e.g., POLYBLEND™ polymer), polyvinyl chloride(PVC), fluoropolymers (e.g., fluorinated ethylene propylene (FEP),perfluoroalkoxy (PFA) polymer, polyvinylidenefluoride (PVDF), etc.),polyetheretherketones (PEEKs), silicones, and copolymers andcombinations (e.g., blends) thereof. Examples of polyamides includenylon 6 (e.g., ZYTEL® HTN high performance polyamides from DuPont™),nylon 11 (e.g., RILSAN® B polyamides from Arkema Inc.), and nylon 12(e.g., GRILAMID® polyamides from EMS-Grivory, RILSAN® A polyamides fromArkema Inc., and VESTAMID® polyamides from Degussa Corp.). Otherpolymers and/or non-polymeric materials may also be used in a catheter.Moreover, any of the materials (e.g., polymers) that are used in acatheter may be combined (e.g., blended), if it is suitable to do so.

In certain variations, a catheter may comprise one or more reinforcedpolymers. For example, a catheter may comprise one or more polymersreinforced with one or more metals and/or metal alloys (e.g., stainlesssteel or a shape memory metal such as Nitinol). Polymers may also bereinforced with textile and/or metal meshes, braids, and/or fibers. Insome variations, a catheter may comprise one or more polymer compositescomprising one or more particulate or fibrous fillers. When compositesare used, the fillers may be selected to impart a variety of physicalproperties, such as toughness, stiffness, density, and/or radiopacity.For example, a catheter may comprise a polymer composite comprisingbarium sulfate (BaSO₄), which may impart the catheter with radiopacity.

As described above, in some variations, a catheter (e.g., a diagnosticcatheter, a visualization catheter, a chord manipulation catheter, aguide catheter, etc.) may be formed of multiple polymers. As an example,a catheter may be formed of a blend of different polymers, such as ablend of high-density polyethylene (HDPE) and low-density polyethylene(LDPE). As another example, a catheter may be formed of differentpolymers having different durometers. For example, a catheter mayinclude different durometer polymers along its length. As an example, incertain variations, a catheter may have a proximal shaft comprising a 72Shore D Durometer Nylon, a distal transition segment comprising a 50Shore D Durometer Nylon, a distal segment comprising a 35 Shore DDurometer Nylon, and an atraumatic tip comprising a 25 Shore D DurometerPEBAX® polymer. As another example, in some variations, a catheter maycomprise multiple different segments or portions comprising PEBAX®polymers having different durometers, such as PEBAX® 35D polymer, PEBAX®40D polymer, PEBAX® 55D polymer, PEBAX® 63D polymer, PEBAX® 72D polymer,or a combination of PEBAX® 72D polymer and PEBAX® 35D polymer. In acatheter comprising different segments or portions with differentdurometer polymers, the segments or portions may all have the samelength, or at least two of the segments or portions may have differentlengths.

While the wall of a catheter may be formed of a single layer, somevariations of catheters may include walls having multiple layers (e.g.,two layers, three layers, etc.). For example, FIG. 4 shows a catheter(401) (discussed in further detail below) comprising an outer catheterwall (457) common to both its proximal section (440) and its distalsection (456), as well as an inner reinforcing wall (458) that isprovided only for proximal section (440). Outer catheter wall (457) may,for example, comprise one or more flexible polymers. Inner reinforcingwall (458) may be formed, for example, from a braided or woven mesh(e.g., a polymer or metal braided or woven mesh). This may help tostiffen the proximal section (e.g., providing catheter (401) withenhanced pushability). Additional detail regarding catheter (401) isprovided below.

In some variations, a catheter may include at least two sections thatare formed of different materials and/or that include different numbersof layers. Additionally, certain variations of catheters may includemultiple (e.g., two, three) lumens. Catheter lumens and/or walls may,for example, be lined and/or reinforced (e.g., with braiding orwinding). The reinforcing structures, if any, may comprise anyappropriate material or materials. For example, they may comprise one ormore metals and/or non-metals. In certain variations, they may compriseone or more polymers having a relatively high durometer.

As discussed above, during a mitral valve repair procedure, a diagnosticcatheter may be advanced into the subannular valve region along aparticular path. The path may, for example, be designed to limit thelikelihood of the diagnostic catheter becoming trapped or blocked alongthe way (e.g., by chordae tendineae). A guidewire may be advanced fromthe diagnostic catheter and along the subannular groove. FIG. 5illustrates one variation of a path that may be used by a diagnosticcatheter and guidewire. Of course, any path that may be successfullyused by a diagnostic catheter may also be appropriate for use by, forexample, a guide catheter or a visualization catheter, or any otherappropriate catheter.

As shown in FIG. 5, a path (500) follows an anterior approach to thesubannular groove region of a heart (502). While an anterior approach isshown, in some variations, a posterior approach may alternatively beused. Path (500) includes bracing points (e.g., bracing point (503))against the greater curvature of the aortic arch (504) and within theascending aorta (506). These bracing points may, for example, provideenhanced stability and support to the diagnostic catheter and/orguidewire (e.g., by contacting the tissue wall) when they are advancedand positioned within the heart. The bracing points may also allow thediagnostic catheter to be positioned relatively easily (e.g., withminimal or no adjustment after being routed to the target site). Itshould be understood that while certain exemplary bracing points areshown, a catheter path may alternatively or additionally include otherbracing points. Moreover, any appropriate number of bracing points maybe employed, and in some cases a catheter path may not have any bracingpoints.

FIG. 5 also shows the mitral valve region (508) of heart (502). Asshown, path (500) curves along a portion of mitral valve region (508).Although not shown, in some cases a guidewire may be routed around asubannular groove and may cross back across the aortic valve in theantegrade direction. This may, for example, enhance the stability of theguidewire's positioning, and/or may provide an extra indication ofwhether the guidewire is positioned behind the chordae tendineae (sinceit may be easier to cross back across the aortic valve if the guidewireis positioned behind the chordae tendineae).

Visualization Devices and Methods

In some instances, one or more variations of methods may be used tovisualize the advancement and positioning of a catheter, such as adiagnostic catheter or guide catheter, within the heart. These methodsmay be used, for example, to help properly position and orient thecatheter. In certain variations, one or more of the methods describedherein may be used to visualize a subannular groove region of a heartvalve, such as a subannular groove region of a mitral valve or asubannular groove region of a tricuspid valve. As discussed below, someof the methods may employ X-ray fluoroscopy to visualize the subannulargroove region, while other methods may employ ultrasound techniques. Incertain variations, a combination of visualization methods may be usedto visualize a subannular groove region. As an example, a method ofvisualizing a subannular groove region (or another region of a heart, ora non-cardiac region) may use both X-ray fluoroscopy and ultrasound. InX-ray fluoroscopy, X-ray images are obtained using an X-ray source and adetector placed on opposite sides of the patient. The X-ray sourceirradiates a first side of the patient, and the detector detects X-raysignals transmitted through the patient. In ultrasonography, reflectionsof high-frequency sound waves are used to form an image of a target sitein the body.

In some variations, a visualization method may comprise usingfluoroscopic projections to help guide a catheter into a region of aheart, such as a subannular groove region. The method may comprisevisualizing the subannular groove region and catheter placement thereinusing a pattern created by injected contrast agent as a fluoroscopiccue. The method may alternatively or additionally be used to assessguidewire placement in the subannular groove region. For example, acatheter may be advanced to a position proximate to the subannulargroove region of a heart valve (e.g., a mitral valve) and a radiopaquecontrast agent may be delivered from the catheter (e.g., through a portin the catheter). The presence of the contrast agent in the heart mayallow the subannular groove region to be visualized under X-rayfluoroscopy. This, in turn, may allow one or more catheters, otherdevices, and/or implants to be accurately positioned and/or deployed inthe subannular groove region. More specifically, once the contrast agenthas been delivered to the subannular groove region, one or more spatialdistribution patterns of the contrast agent, such as a series oftime-dependent distribution patterns, may be viewed under X-rayfluoroscopy. As an example, a series of spatial distribution patternsmay be acquired at spaced-apart time intervals using X-ray fluoroscopy.The position and/or orientation of a catheter may then be determinedand/or adjusted based upon the observed spatial distribution patterns ofthe radiopaque contrast agent.

In some variations of visualization methods, a first catheter may beused to inject one or more radiopaque materials into a subannular grooveregion of a heart, thereby allowing X-ray fluoroscopy to be used toidentify the location of the subannular groove. The first catheter maythen be used to guide or position a second catheter within at least aportion of the subannular groove. For example, the first catheter may beinserted at least partially into the subannular groove after thelocation of the subannular groove has been identified. Then, the secondcatheter may be advanced over or within the first catheter and into thesubannular groove. After the advancement of the second catheter, thefirst catheter may be withdrawn while the second catheter remains inplace, allowing for the insertion of other tools or catheters into thesubannular groove via the second catheter.

In some variations, a C-arm X-ray fluoroscope may be used to obtainfluoroscopic images. Examples of commercially available C-arm X-rayfluoroscopes include those provided by GE (e.g., the INNOVA™ X-raysystem), Philips (e.g., the Eleva system), and Siemens (e.g., the AXIOMsystem or the Artis zee multi-purpose system). During use, a C-arm X-rayfluoroscope may be manipulated in certain ways and according to certainparameters, in order to obtain a desired fluoroscopic image.

For example, FIG. 6A is an illustration of a top view of a human subject(600) on an operating table (602), the subject having a head (604) andfeet (606) and (608). When the subject is positioned on the operatingtable, the region in which head (604) is located may be referred to asthe cranial region, while the region in which feet (606) and (608) arelocated may be referred to as the caudal region. Referring also now toFIGS. 6B and 6C, the top portion (611) of the C-arm (610) of a C-armX-ray fluoroscope (612) may be positioned toward or away from thecranial region during imaging. In other words, top portion (611) may beupright, or may be rotated along arrow (616) (FIG. 6C) by as much as45°, either toward the cranial region or away from the cranial region.When tilted toward the cranial region, top portion (611) is said to bein a cranial (CRA) orientation. When tilted away from the cranialregion, top portion (611) is said to be in a caudal (CAU) orientation.

Additionally, operating table (602) defines a horizontal axis (HAX), aswell as a vertical axis (VAX) at a 90° angle with respect to thehorizontal axis. As shown in FIG. 6B, the subject has a right side (R)and a left side (L). Top portion (611) of C-arm (610) may be tiltedtoward right side (R) or left side (L), as indicated by arrow (614) (inwhich dashed lines indicate that the arrow is going into the plane ofthe paper), by an angle of at most 90°. In other words, the C-arm may betilted by as much as 900° o left side (L), or as much as 90° to rightside (R). Of course, top portion (611) of C-arm (610) may also tilt byany amount between and including 0° and 90°, to either side. When thetop portion of the C-arm is tilted toward left side (L), the angle isconsidered to be a left anterior oblique (LAO) angle, and when the topportion of the C-arm is tilted toward right side (R), the angle isconsidered to be a right anterior oblique (RAO) angle.

FIG. 6D shows an illustration of a short-axis view of a mitral valvesubvalvular space (650) of a heart (652). As used herein, a “short-axisview” refers to an en face perspective view of the ventricular spacebelow either the mitral valve or the tricuspid valve. It should be notedthat the imaging methods described here with respect to the mitral valvemay also be applied to the tricuspid valve—however, the angles orprojections for the tricuspid valve may be different from those for themitral valve.

When it is desired to provide a short-axis view using a C-arm X-rayfluoroscope, the subject may be positioned in the supine position, andthe fluoroscope may be oriented in a left anterior oblique (LAO)/caudal(CAU) orientation. In some variations in which an LAO/CAU orientation isused, the minimum LAO value may be 30° and/or the maximum LAO value maybe 50°. Alternatively or additionally, in certain variations in which anLAO/CAU orientation is used, the minimum CAU value may be 10 and/or themaximum CAU value may be 30°. Another orientation that may be used toprovide a short-axis view is the left anterior oblique (LAO)/cranial(CRA) orientation. In some variations in which an LAO/CRA orientation isused, the LAO value may be 48° and/or the CRA value may be 00. Otherappropriate values may also be used.

FIG. 6E shows a short-axis view of mitral valve subvalvular space (650)upon injection of a radiopaque contrast agent (654) from a catheter(656). The resulting image may be used to position, and/or to verify thepositioning of, another catheter (not shown) within the subannulargroove. For example, a guide catheter or an anchor deployment cathetermay be positioned using the image.

FIG. 6F shows a long-axis view of mitral valve subvalvular space (650).As used herein, a “long-axis view” refers to a profile perspective ofthe ventricular space below either the mitral valve or the tricuspidvalve. When it is desired to provide a long-axis view using a C-armX-ray fluoroscope, in certain variations, the fluoroscope may bepositioned in a right anterior oblique (RAO) orientation. In somevariations in which an RAO/CAU orientation is used, the minimum RAOvalue may be 350 and/or the maximum RAO value may be 44°. Alternativelyor additionally, in certain variations in which an RAO/CAU orientationis used, the minimum CAU value may be 0° and/or the maximum CAU valuemay be 3°. In some variations in which an RAO/CRA orientation is used,the minimum RAO value may be 00 or 30°, and/or the maximum RAO value maybe 610 or 500. In certain variations in which an RAO/CRA orientation isused, the minimum CRA value may be 0° and/or the maximum CRA value maybe 50° or 4°. The appropriate angle range for any of the orientationsdescribed herein may depend, for example, on the characteristics of theparticular subject's anatomy that is being imaged.

FIG. 6G shows a long-axis view of mitral valve subvalvular space (650)when radiopaque contrast agent (674) is injected into mitral valvesubvalvular space (650) using a catheter (676). The resultingfluoroscopic image may be used to position, and/or to verify thepositioning of, catheter (676) and/or one or more other devices (e.g.,catheters) within the subannular groove. For example, the image may beused to position a guide catheter or an anchor deployment catheter.

In some variations, a physician or other operator may alternate betweenshort- and long-axis views of a subvalvular space in order to obtainaccurate positioning of a catheter within the subvalvular space. Forexample, a physician may start with a short-axis view (e.g., using anLAO/CAU orientation), and then may switch to a long-axis view (e.g.,using an RAO/CRA orientation). Alternatively, the physician may startwith a long-axis view and then switch to a short-axis view. A physicianor other operator may switch back and forth between different viewsuntil the desired positioning has been achieved.

FIGS. 7A-7C and 8A-8F further illustrate the use of a radiopaquecontrast agent to visualize the subannular groove of a heart. Aspreviously described, during such a visualization procedure, a cathetermay inject radiopaque contrast agent into the subannular groove of aheart. The contrast agent may, for example, be delivered from thecatheter through a delivery port. In some variations, the delivery portof the catheter may be in the form of an opening in a wall portion ofthe catheter proximal to the distal end or tip of the catheter, or maybe in the form of an opening in the distal end or tip itself. If thedelivery port is not inserted against or into the subannular groove,contrast agent delivered through the delivery port may diffuse out intothe left ventricular chamber. This diffusion of the contrast agent mayfunction as a visual indication (under X-ray fluoroscopy) that thecatheter is not properly seated in or against the subannular groove. If,on the other hand, the contrast agent is channeled into the subannulargroove when the contrast agent is delivered into the heart, then thismay indicate that the catheter is properly seated in or against thesubannular groove.

FIGS. 7A-7C provide an illustrative depiction of an exemplaryvisualization method. First, FIG. 7A provides a short-axis view of anannulus (A) and the corresponding subannular groove (SAG). In FIG. 7A, acatheter (701) has accessed the left ventricle (LV), but the deliveryport (703) at the distal end (702) of catheter (701) is not seated in oragainst the subannular groove (SAG). As a result, when contrast agent(705) is delivered through delivery port (703), the contrast agentdiffuses throughout the left ventricular chamber, as indicated by thehatched region. Conversely, and as illustrated in the short-axis viewprovided in FIG. 7B and the long-axis view provided in FIG. 7C, ifdelivery port (703) is seated in or against the subannular groove, ascontrast agent (705) is ejected out of delivery port (703), the contrastagent will trace out a defined streak or arc (704) in the subannulargroove, indicated by cross-hatching. Under X-ray fluoroscopy, thisstreak or arc (704) provides a visual indication of proper positioningof catheter (701) in or against the subannular groove (SAG).

When a distal portion (e.g., the distal end) of a catheter isradiopaque, the position of the distal portion relative to theventricular wall and subannular groove may be determined by its positionwithin the contrast pattern (e.g., streak or arc) created by injectingradiopaque contrast agent into the subannular groove. For example,referring to the short-axis view shown in FIG. 7B, the outer peripheryof streak or arc (704) defines the interior surface of the leftventricular wall (VW) (endocardium), which is proximate to the annulus.Thus, in the short-axis view, as radiopaque distal end (702) of catheter(701) gets closer to the ventricular wall or annulus, the amount ofcontrast between distal end (702) and the outer periphery of contraststreak or arc (704) will decrease. Similarly, and referring to thelong-axis view shown in FIG. 7C, the closer radiopaque distal end (702)of catheter (701) is to the ventricular wall and therefore to theannulus, the less contrast there will be between the superior border(706) of streak or arc (704) and radiopaque distal end (702) of catheter(701).

Any suitable radiopaque contrast agents may be used in the methodsdescribed here. Generally, radiopaque contrast agents may be used in anyway that improves the ability to distinguish certain tissue (e.g., thesubannular groove region) from other tissue, or any portion of animplant, catheter, anchor deployment device, tool or the like from thesubannular groove region or other tissue. Radiopaque contrast agentsincrease the absorption of X-rays and result in a positive contrast inX-ray fluoroscopy (i.e., an opaque image or shadow where the radiopaquecontrast agent is present). Radiopaque contrast agents typically mayinclude any soluble or insoluble compound that increases absorption ofX-rays. Some variations of radiopaque contrast agents may compriseiodine. For example, a contrast agent may comprise an aqueous solutionof one or more iodine-containing salts, such as: a salt of a diatrizoate(e.g., sodium diatrizoate such as HYPAQUE™ contrast medium, or sodiummeglumine diatrizoate such as RENOGRAFIN-76™ contrast medium); a salt of5-acetamido-2,4,6-triiodo-N-methylisophthalamic acid (e.g., theN-methylglucamine salt, meglumine iothalamate (e.g., CONRAY™ contrastagent)); a salt of acetrizoate (e.g., sodium acetrizoate such as UROKON™contrast medium); a salt of 3-5-diiodo-4-pyridone-N-acetic acid (e.g.,the diethanolamine salt, iodopyracet such as DIODRAST™ contrast medium);or a salt of ioxaglate (e.g., sodium meglumine ioxaglate such asHEXABRIX™ contrast medium). In certain variations, combinations ofradiopaque contrast agents may be used. As an example, an aqueoussolution of diatrizoate meglumine and diatrizoate sodium may be used insome instances. In some variations, nonionic radiopaque contrast agentsmay be used. For example, iohexol (e.g., OMNIPAQUE™ contrast agent) andiodixanol (e.g., VISIPAQUE™ contrast medium) may be used in aqueoussolution.

The type of contrast agent that is used, as well as its concentration,may be selected based on any of a variety of different factors, such asthe X-ray absorption properties of the radiopaque compound (e.g.,determined in part by the number of iodine atoms), the irradiationscheme and image capture scheme to be used (e.g., the intensity of theX-ray irradiation used to form the image, the time duration of the X-rayacquisition, the type of detector used, and the degree of contrastdesired), and/or other issues specific to the patient (e.g., kidneydisease, or the presence of other systemic drugs). In some cases inwhich a significant amount of radiopaque contrast agent is desirable, acontrast agent filter may be used (e.g., to minimize kidney damage).

FIG. 8A is a fluoroscopic image of a short-axis view of a subannulargroove obtained using a radiopaque contrast agent. As shown there,contrast agent (800) has been injected into the subannular groove, and aguide catheter (802) and guidewire (804) have been positioned in thesubannular groove. Guidewire (804) circumnavigates the subannulargroove. The alignment of the guide catheter and the guidewire with theedge of the contrast agent is indicative of proper positioning of theguide catheter and guidewire in the subannular groove. Similarly, FIG.8B is another fluoroscopic image of a short-axis view of a subannulargroove obtained using a radiopaque contrast agent (806). As shown there,a catheter (808) and a guidewire (810) have been positioned in asubannular groove, as indicated by the alignment of catheter (808) andguidewire (810) with the edge of contrast agent (806). As shown in FIG.8B, guidewire (810) circumnavigates the subannular groove. FIG. 8C is anadditional fluoroscopic image of a short-axis view of a subannulargroove showing the positioning of a guide catheter (812) such that theguide catheter is aligned relative to an accompanying injection ofcontrast agent. FIG. 8E is a fluoroscopic image of a long-axis view of asubvalvular space of an ovine heart (beneath the mitral valve), in whicha catheter (850) is positioned. FIG. 8F is a fluoroscopic image of ashort-axis view of a subannular groove region of an ovine heart, showingthe position of a catheter (862) and a guidewire (864) in the subannulargroove region.

In some variations of methods, one or more radiopaque contrast agentsmay be injected into a subannular groove region of a heart to helpidentify the location of an implant (all or a portion of which may beradiopaque) in the subannular groove region. First, X-ray fluoroscopymay be used to obtain one or more spatial distribution patterns of theradiopaque contrast agent or agents. Then, the distribution pattern orpatterns may be used to visualize a location and/or orientation of animplant (e.g., an anchor) relative to the subannular groove region.Where a radiopaque image of the implant does not overlap with theradiopaque streak or are from the contrast agent(s), that portion of theimplant has not been reached by the streak. For example, that portion ofthe implant may be located in a region that is inaccessible by thestreak (e.g., embedded into a ventricular wall or located outside of thesubannular groove). Any suitable implant or combination of implantshaving sufficient radiopacity may be viewed in this way. Some viewableimplants may comprise at least one anchor, such as two or more anchors(e.g., that are coupled together by a tether). One or more of theanchors, or one or more portions thereof, and/or one or more tethers,may be radiopaque. Moreover, in certain variations, all or a portion ofa catheter may be radiopaque.

In some variations, one or more tissue anchors that are at leastpartially positioned in the subannular groove may be visualized, asillustrated in the short-axis view shown in the fluoroscopic image ofFIG. 8D. As shown there, a catheter (890) has been positioned in asubannular groove of a heart, and anchors, such as an anchor (892), havebeen deployed into the subannular groove region. The positioning of theanchors beyond the edge of the contrast pattern in FIG. 8D indicate thatthe anchors are embedded in the myocardium, and that they are notexposed to the ventricular chamber.

Implants, portions of implants, catheters, or portions of catheters usedin the methods described here may be rendered radiopaque by any suitablemethod. For example, implants may be formed of one or more biocompatibleradiopaque metals or metal alloys, such as Nitinol. Some implants may becoated or partially coated (e.g., by plating or sputtering) with one ormore biocompatible metals, such as gold, silver, titanium, tantalum, oralloys thereof. Certain variations of implants may be filled with one ormore radiopaque materials, such as barium sulfate (BaSO₄), bismuthtrioxide (Bi₂O₃), or a radiopaque metal. Implants or catheters may bemade with a polymer or coated with a polymer or ink that contains aradiopaque material, such as a polymer composite containing metalmarkers (e.g., tungsten markers) and/or another radiopaque material suchas barium sulfate or bismuth trioxide. Polymers used to make implants orcatheters radiopaque may also have chemically bound radiopaque moieties(e.g., iodine-containing moieties), to reduce the possibility of theradiopaque material leaching into surrounding areas.

Any appropriate catheter or other device may be used to deliverradiopaque material, such as radiopaque contrast agent, to a targetregion (e.g., a subannular groove) in a heart. For example, FIG. 9 showsa variation of a catheter (901) that may be used to deliver radiopaquecontrast agent to a subannular groove region of a heart. Catheter (901)may be flexible and/or steerable. As shown in FIG. 9, catheter (901) hasa delivery port (914) in its distal portion (918), near its distal end(922). Delivery port (914) is configured to deliver one or more contrastagents therethrough. Although FIG. 9 depicts delivery port (914) aspositioned along a side wall (921) of catheter (901) near distal end(922), other variations of catheters may include one or more contrastagent delivery ports positioned in their distal end. Catheter (901) alsocomprises an input port (916) near its proximal end (920). While notshown here, some variations of catheters may alternatively oradditionally comprise one or more input ports located at their proximalend, and/or in one or more other locations of the catheter. Input port(916) includes a plunger (923) adapted to force one or more liquids intoand through a tube or syringe body (924), so that the liquid eventuallyexits the catheter through delivery port (914). While one variation ofan input port has been shown, other variations of input ports, includinginput ports suitable for injecting a solution, may be used asappropriate.

Methods for visualizing a heart valve region, such as the subannulargroove region, as well as implants and/or devices within the heart valveregion, may employ any suitable image capture techniques. As describedabove, in some variations, X-ray images may be obtained using X-rayfluoroscopy. In certain variations, more than one irradiation angle maybe used to obtain X-ray images. For example, as shown in FIGS. 7A-7C and8A-8F, images may be collected along the short axis and/or long axis ofa patient's heart.

In certain variations, images taken from multiple angles may be used toconstruct a three-dimensional image of a heart valve region, such as thesubannular groove, surrounding anatomy, and/or implants. In addition,X-ray fluoroscopy may be used to create a real-time image (i.e., as theradiopaque substance is injected into the patient). X-ray fluoroscopymay also be used to create a series of time-dependent images (e.g., attime intervals of 60 Hz, 30 Hz, 10 Hz, 1 Hz, 0.5 Hz, or 0.1 Hz), tovisualize the time-dependent dispersion of the radiopaque materialthroughout the patient. Images may be sampled at regularly spaced timeintervals in an automated manner, or in any sequence of predeterminedintervals. For example, the intervals may be programmed into acontroller of an X-ray fluoroscopy system and/or may be provided in asequence manually determined by an operator (e.g., a physician). TheX-ray fluoroscopy signals and/or images produced from X-ray fluoroscopysignals may be analyzed or processed digitally and/or using analogtechniques. Any suitable method or combination of methods (e.g.,amplification, filtering to enhance contrast or reduce noise, extraneoussignals, scattered signals, or the like, or image correction to accountfor geometrical effects, or the like) may be employed. In certainvariations, the acquisition of X-ray images may be synchronized (e.g.,triggered) with the delivery of the radiopaque material to allow formore precise determination of time-dependent measurements.

In some variations, a fluoroscopic visualization method may employ bothshort- and long-axis views in assessing placement of a catheter in asubannular groove region (e.g., in the subannular groove itself) of aheart. As discussed above, the short-axis view generally provides an enface perspective of the ventricular space below the mitral valve, whilethe long-axis view generally provides a profile perspective of theventricular space below the mitral valve. When these two views areimaged, injection of contrast agent into the imaged site will generallyhighlight the border between the ventricular wall and the ventricularchamber. The catheter may then be referenced against the contrastpattern to determine whether the catheter is, for example, well-apposedagainst the endocardium, lodged or deployed in the myocardium, levelwith the mitral valve, or diverging from the mitral valve. Devices thatare advanced through the catheter and around the subannular grooveshould generally be aligned with the edges of the contrast patternsprovided by the short- and long-axis views. Thus, the contrast patternsmay be used to determine whether alignment is proper.

Guidewire placement may also be evaluated using the above method.Typically, a guidewire that has successfully circumnavigated thesubannular groove (and, in some cases, that crosses the aortic valve inthe antegrade direction) will be aligned with the edge of the short-axisview in the contrast pattern and will be very stable. This alignment mayalso provide a strong indication that the guidewire is apposed againstthe endocardium, and that it does not interfere with the chordaetendineae. Lack of alignment of the guidewire with the contrast patternin the short-axis view may be indicative of interference with chordaetendineae or migration toward the center of the ventricular chamber.Additionally, dynamic behavior showing a lack of stability of theguidewire may also suggest that the guidewire is not entirely situatedbehind the chordae tendineae and against the endocardium.

While visualization methods using X-ray fluoroscopy have been described,other variations of methods may alternatively or additionally be used tovisualize a region of a heart. As an example, ultrasonography may beemployed to visualize a region of a heart. For example, in somevariations, a visualization method may include advancing a catheter(e.g., a steerable catheter) to a position proximate to or at leastpartially within the subannular groove of a heart valve. The cathetermay comprise at least one ultrasonic transducer or probe (e.g.,positioned within at least one lumen of the catheter and/or in a distalportion of the catheter). The transducer may be temporarily orpermanently coupled (e.g., secured, joined, or linked) to the catheter.During use, the transducer may transmit and receive ultrasonic energy,thereby allowing for visualization of structures proximate thetransducer (e.g., anatomy such as the subannular groove or structuressurrounding the subannular groove, implants, the catheter, and therelative positions thereof, such as the relative positions of theanatomy and the catheter). In some variations, a method may includevisualizing the location and/or orientation of a catheter, anddetermining and/or adjusting the position of the catheter accordingly.The catheter may continue to be adjusted until the desired orientationand position have been achieved.

The ultrasonic transducer or transducers may be used to visualize and/orposition the catheter at a target site, such as in the subannular grooveof the mitral valve or tricuspid valve. In some variations, thevisualization catheter may be a pre-formed or pre-shaped catheter, or asteerable catheter that may provide enhanced control and placement ofthe ultrasonic transducer (and, therefore, enhanced viewing). In somevariations of methods, the subannular groove of a heart valve region maybe circumnavigated with the distal end of a visualization catheter tovisualize the surrounding region (e.g., the subannular groove itself,the anatomy surrounding the subannular groove such as the annulus or themitral valve, and/or implants near or in the subannular groove, such asimplants used to repair a heart valve annulus).

FIG. 10 is an illustrative depiction of a portion of a heart, showing acatheter (1020) comprising an ultrasonic transducer (1044). As shownthere, catheter (1020) (and, therefore, ultrasonic transducer (1044))has been positioned in the subannular groove in the left ventricle (LV)of the heart, generally below the annulus (A) and between theventricular wall (VW) and chordae tendineae (CT). The area enclosed bythe dashed contour (1010) in FIG. 10 is a cross-section of the localizedfield of view provided by ultrasonic transducer (1044). This localizedfield of view may be used, for example, to establish the catheter'sposition with respect to the endocardium and/or the mitral valve. Thecatheter may be guided into the subannular groove using signal output(e.g., real-time output) from the transducer. The location and/ororientation visualized with the transducer may be used to determine theposition of the catheter and/or to adjust the position of the catheterrelative to the valve leaflets, chordae tendineae, and/or other anatomy.For example, the visualized location or orientation may be used toposition and/or steer the catheter beneath the mitral valve leaflets andbehind chordae tendineae.

Any suitable ultrasonic transducer or combination of ultrasonictransducers may be used in the methods described here. For example,piezoelectric transducers or capacitive micro-electromechanicalultrasonic transducers may be used. In some variations, the transducersmay operate (i.e., emit and detect ultrasound frequencies) at about 5MHz, about 10 MHz, about 15 MHz, about 20 MHz, about 25 MHz, about 30MHz, about 35 MHz, about 40 MHz, about 45 MHz, or about 50 MHz. A higherfrequency transducer may be used where greater contrast is required.Moreover, transducers having any of a variety of appropriate physicaldimensions may be used. For example, in some variations, a transducermay be sized so that it can be disposed within a catheter (e.g., withina lumen of the catheter). As an example, in certain variations, atransducer may have a cross-sectional dimension that allows it to bedisposed within a catheter having an inner diameter of about 0.5millimeter to about 8 millimeters (e.g., about 0.5 millimeter, about 0.6millimeter, about 0.7 millimeter, about 0.8 millimeter, about 0.9millimeter, about 1.0 millimeter, about 1.1 millimeters, about 1.2millimeters, about 1.3 millimeters, about 1.4 millimeters, about 1.5millimeters, about 2 millimeters, about 3 millimeters, about 4millimeters, about 5 millimeters, about 6 millimeters, about 7millimeters, or about 8 millimeters). In some variations, the size of atransducer may be selected according to the desired spatial resolution.For example, a relatively small transducer may be used to visualizerelatively small features of the anatomy in or surrounding thesubannular groove of a heart, and/or relatively small features ofimplants. In certain variations, a transducer may be positioned within acatheter, facing radially outward from the center of the catheter. Insome variations, a transducer may be rotated and or translatedsubstantially independently of a catheter. For example, the transducermay be secured to a connector threaded through a lumen of the catheter.The transducer may be translated by translating the connector along thelength of the catheter. Alternatively or additionally, the connector maybe rotated to rotate the transducer around an axis defined by theconnector, without causing corresponding movement by the catheter body.

Some variations of catheters may comprise more than one ultrasonictransducer (e.g., to expand the viewable area). For example, a cathetermay comprise an array of transducers. Transducers may be arranged in alongitudinal array (e.g., along an axis generally parallel to the lengthof the catheter) and/or in a ring-like array (e.g., circumferentiallyaround the distal tip of the catheter, where each transducer's output isgenerally emitted in a distal direction or radially outward from thecatheter). Other appropriate transducer arrangements may also be used.In variations in which more than one transducer is used, each transducermay be individually addressable. Moreover, in certain variationsincorporating more than one transducer, some transducers may be used totransmit ultrasonic energy, while other transducers may be used toreceive reflected ultrasonic energy from surrounding structures.

Additional variations of methods are described here. These methods maybe used to ascertain or verify the position of a guide catheter in asubannular groove of a heart, and/or to position a guide catheter in thesubannular groove. In some variations, a method may comprise advancing afirst catheter comprising an ultrasonic transducer distally through aguide catheter positioned in the vicinity of the subannular groove of aheart valve. The first catheter may be advanced sufficiently through theguide catheter such that the ultrasonic transducer extends beyond adistal end of the guide catheter. The ultrasonic transducer may then beused to view or verify the location of the guide catheter relative to aregion surrounding the distal end of the first catheter by transmittingand receiving ultrasonic energy. The viewable region may include, forexample, the subannular groove, anatomical structures near thesubannular groove (e.g., the annulus or the mitral valve), implantspositioned near or in the subannular groove, and/or portions of thefirst catheter and the guide catheter.

In some variations, the first catheter may alternatively or additionallybe used to position or adjust the position of the guide catheter in thesubannular groove. In some such variations, after the first catheter hasbeen advanced distally through the guide catheter such that thetransducer extends distally from the distal end of the guide catheter,the first catheter may be advanced to a position proximate to, or atleast partially within, the subannular groove. The transducer may beused to visualize a region in and/or around the subannular groove. Theguide catheter may then be advanced to a position proximate to or atleast partially within the subannular groove by sliding the guidecatheter along the first catheter. In certain variations, once the guidecatheter is positioned as desired within the subannular groove, thefirst catheter may be withdrawn. The guide catheter may then be used toaccess the subannular groove with other catheters, devices, and/ortools.

As an example, FIG. 11A depicts the advancement of a visualizationcatheter (1101) through a guide catheter (1182). As shown there,visualization catheter (1101), which comprises an ultrasonic transducer(1144), is distally advanced until ultrasonic transducer (1144) extendsjust beyond the distal end (1183) of guide catheter (1182). Once sopositioned, ultrasonic transducer (1144) may be used to view thesurrounding anatomy. In some variations, images from ultrasonictransducer (1144) may be used to position the combined visualizationcatheter (1101) and guide catheter (1182) within the subannular groove.Referring now to FIG. 11B, visualization catheter (1101) may becircumnavigated around the subannular groove. As visualization catheter(1101) is threaded through the subannular groove, nearby anatomicalstructures and implants may also be imaged. Further, guide catheter(1182) may be extended through the subannular groove (e.g., along withvisualization catheter (1101) or over visualization catheter (1101),with visualization catheter (1101) acting as a guidewire or rail).Thereafter, visualization catheter (1101) may be withdrawn while guidecatheter (1182) remains in place (e.g., to receive other catheters,devices, and/or tools). Alternatively or additionally, in certainvariations, visualization catheter (1101) may be used to guide aguidewire around the subannular groove, behind the chordae tendineae.

Catheters comprising one or more ultrasonic transducers may comprise,for example, a proximal section that is joined to a distal section, andmay also comprise a transition section between the proximal and distalsections. In some variations, the distal section may include a windowregion that is at least partially transparent to ultrasonic energy. Theultrasonic transducer or transducers may be disposed in the windowregion. In certain variations, the catheter may include one or moretensioning elements that pass through a first lumen of the catheter andthat are secured to the distal section. Tension may be applied to thetensioning element or elements to steer the distal section of thecatheter. In some variations, the distal section may be more flexiblethan the proximal section. In certain variations, the tensioning elementor elements may be tensioned to enable movement (i.e., steering) of thedistal section without substantially moving or disturbing the proximalsection. In some variations, a catheter may include at least two lumens,with a tensioning element disposed in one lumen, and an ultrasonictransducer disposed in another lumen.

FIG. 12 illustrates an example of a suitable catheter that may be usedwith one or more of the methods provided herein. As shown there, acatheter (1201) has a distal section (1256) joined to a proximal section(1240), with a dashed line denoting the boundary between the twosections. The distal section may be joined with the proximal section inany suitable manner. For example, the distal and proximal sections mayform a continuous or integral unit. Alternatively, the distal andproximal sections may be in the form of two distinct units that havebeen attached to each other (e.g., by bonding through fusion or with anadhesive, or by mechanical coupling). In some variations, the cathetermay comprise a transition section interposed between the proximal anddistal sections, where the transition section joins the proximal anddistal sections to each other. Again, the distal section, transitionsection, and proximal section may form a single continuous or integralunit, or may comprise discrete units that have been attached together.In the variation shown in FIG. 12, the proximal and distal sections havea common wall (1257), but the proximal section has an extra reinforcingwall (1258). Distal section (1256) includes a window region (1250).Optionally, and as illustrated, distal section (1256) may include a tipregion (1252) distal to the window region (1250), where the tip regioncan be softer or more flexible than the bulk of the distal section,and/or can have a reduced outer diameter relative to the window region.

Catheter (1201) comprises at least one ultrasonic transducer (1244). Insome variations, and as shown, ultrasonic transducer (1244) may besecured to a connector (1246) that passes through a lumen (1242) of boththe distal and proximal sections of the catheter. In some catheters,connector (1246) may be used to position ultrasonic transducer (1244).For example, the connector may be adapted to translate the ultrasonictransducer longitudinally along the length of the catheter (e.g., toposition the transducer longitudinally within the window region), toremove the transducer from the window region, and/or to remove thetransducer from the catheter altogether. Some connectors may positionthe transducer by rotation (e.g., the transducer may be positioned byrotation around an axis defined by the connector). Thus, in certainvariations in which lumen (1242) houses the transducer, the innerdiameter of lumen (1242) may be large enough to accommodate rotation ofthe transducer. For example, in some variations, lumen (1242) may havean inner diameter of at least about 0.5 millimeter (e.g., about 0.5millimeter, about 0.6 millimeter, about 0.7 millimeter, about 0.8millimeter, about 0.9 millimeter, about 1.0 millimeter, about 1.1millimeters, about 1.2 millimeters, about 1.3 millimeters, or evenlarger). In certain variations, connector (1246) may function as arotation shaft, rapidly and continuously rotating the transducer aboutan axis defined by the connector. The connector may automatically rotatethe transducer (e.g., at a fixed or programmed velocity or interval, orin response to a trigger), or the connector may be manually controlledto rotate the transducer. In some variations, the connector may rotatethe transducer under a combination of manual and automatic control.Lumen (1242) may be coated or lined with one or more lubricioussubstances, such as high-density polyethylene (HDPE) orpolytetrafluoroethylene (PTFE). This may, for example, cause the lumento provide a relatively low-friction environment in which connector(1246) and/or ultrasonic transducer (1244) may translate and/or rotate.

Referring still to FIG. 12, transducer (1244) is disposed in windowregion (1250) of distal section (1256). Window region (1250) is at leastpartially transparent to the ultrasonic energy emitted and detected bythe transducer. For example, window region (1250) may comprise one ormore windows that can transmit ultrasonic energy having the frequencyemitted and detected by the transducer. In some variations, the windowsmay be in the form of openings in the catheter wall that allow passageof ultrasonic energy. Alternatively or additionally, the window regionmay comprise one or more windows comprising a thin polymer layer (e.g.,a polymer thin film having a thickness of about 0.002 inch, about 0.003inch, about 0.004 inch, about 0.005 inch, about 0.006 inch, or about0.007 inch). Examples of polymers which may be suitable for one or morewindows in a window region include polyethylene (e.g., high-densitypolyethylene (HDPE)), nylon (e.g., nylon 6, nylon 11, nylon 12), PEBAX®polymers, polyurethanes, and polyimides. Other suitable materials mayalternatively or additionally be used. In certain variations, thewindows may be continuous with the catheter wall in the window region(e.g., a window may be in the form of a thinned-out region of the wall).In some variations, the windows may be separate elements applied to thewindow region of the catheter, such as thin polymer films secured (e.g.,by fusion, adhesives, or mechanical attachment) over openings in thecatheter. In certain variations, a catheter may include one or morecombinations of different types of windows.

In variations in which a window region comprises multiple windows, thewindows may be configured in any suitable fashion. For example, windowsmay be arranged circumferentially around a catheter, and/orlongitudinally along the length of a catheter. Moreover, window sizes orshapes may vary according to the application. For example, window sizesor shapes may be determined by structural considerations, catheter sizeand/or shape, catheter wall thickness, size and/or number oftransducers, size and/or position of anatomy or implant being viewed, orany combination of factors.

Any suitable ultrasonic transducer or combination of ultrasonictransducers may be used in the catheters, including piezoelectric orcapacitive micro-electromechanical ultrasonic transducers. Thetransducers can operate at, for example, about 5 MHz, about 10 MHz,about 15 MHz, about 20 MHz, about 25 MHz, about 30 MHz, about 35 MHz,about 40 MHz, about 45 MHz, or about 50 MHz. Moreover, transducershaving varying physical dimensions may be used. For example, atransducer may have a cross-sectional dimension that allows it to bedisposed, and in some cases rotated, in a lumen of a catheter.

Referring again to FIG. 12, signals to and from the transducer may alsobe carried by connector (1246). In some variations, connector (1246) maycomprise a single connector that can transmit signals to and from thetransducer and that can position the transducer. In other variations,connector (1246) may comprise multiple connectors, such as one or moreconnectors for positioning the transducer, as well as one or more otherconnectors for transmitting signals to and from the transducer.

Referring still to FIG. 12, as described above, more than one transducermay be used in the catheters described herein. As an example, althoughschematically illustrated as a single block for simplicity, ultrasonictransducer (1244) may comprise one or more arrays of transducers. If anarray of transducers is used, the transducers may be arranged in anysuitable manner. For example, and as described briefly above, transducer(1244) may represent a longitudinal array (e.g., multiple transducerspositioned along an axis generally parallel to the length of thecatheter), or a ring-like array (e.g., transducers positionedcircumferentially around connector (1246), where each transducer'soutput is generally emitted in a distal direction, or each transducer'soutput is generally emitted in a direction radially outward from theinterior of the catheter).

As discussed above, when more than one transducer is used, eachtransducer may be individually addressable. That is, connector (1246)may be adapted to transmit signals to and/or from each transducerindependently. In variations of catheters incorporating more than onetransducer, some of the transducers may be used to transmit ultrasonicenergy, while other transducers may be used to receive reflectedultrasonic energy from surrounding structures. Connector (1246) may beadapted to position more than one transducer independently. For example,connector (1246) may comprise two or more independently translatableand/or rotatable wires, where each wire is connected to a separatetransducer and is adapted to position its connected transducerseparately from the other transducer(s). Further, catheters with morethan one transducer may also comprise more than one connector, whereeach connector is adapted to control (e.g., position and/or transmitsignals to or from) a separate transducer or group of transducers.

Still referring to FIG. 12, a tensioning element (1248) (e.g., a flexortendon such as a polymeric cable) passes through lumen (1242), throughboth the distal and proximal sections of the catheter. Additionally,tensioning element (1248) is secured to the distal section of thecatheter at a securing position (1254). In some variations, thetensioning element may be permanently secured to the distal section(e.g., mechanically locked or bonded), while in other variations, thetensioning element may be removably secured to the distal section (e.g.,using a clip, clamp, hook, or the like). Moreover, some variations ofcatheters may comprise a tensioning element that is secured to thecatheter at more than one location. Alternatively or additionally, acatheter may comprise more than one tensioning element. Tension appliedto the tensioning element, either manually by a medical professional orautomatically, may cause the flexible distal section of the catheter tomove. The tensioning element may be secured to the distal section at anysuitable position that enables the steering of the distal section and/orfine-tuning of the position of the distal section. In general, if thetensioning element is secured near the distal end of the distal section,tension applied to the tensioning element may provide preferentialmovement and more direct control of the distal tip. If the tensioningelement is secured near the window region (as shown in the exampleillustrated in FIG. 12), tension applied to the tensioning element mayprovide more direct control over positioning of the window region. Thesecuring position (1254) for tensioning element (1248) may be located atany suitable position relative to window region (1250) (e.g., proximalto, distal to, or within the window region).

In some variations, proximal section (1240) of catheter (1201) may bestiffer or harder (i.e., may have a higher durometer) than distalsection (1256). The proximal section may be rendered stiffer than distalsection using any suitable method. As an example, in certain variations,the wall of the proximal section may be thicker than the wall of thedistal section. As another example, in some variations, the wall of theproximal section may have structural features that impart increasedstiffness or hardness to the wall. For example, the wall of the proximalsection may be formed from a braided or woven material, or ribs, spinesor the like may extend longitudinally along the wall, transverselythrough the thickness of the wall, or circumferentially around the wall(e.g., in a helical manner). Such structural features may be integral tothe wall (e.g., formed on or in the wall during a molding process), ormay be in the form of one or more separate elements that are added tothe wall (e.g., one or more reinforcing bands, coatings, fibers, meshes,or the like that are applied to the wall).

In some variations, a proximal section of a catheter may comprise a wallincluding multiple layers (e.g., for added stiffness). For example, FIG.12 shows an inner wall (1258) located only in proximal section (1240),which may increase the stiffness of proximal section (1240). The wallsof the proximal section may be made in part or in whole from one or morematerials that are different from the material(s) of the walls of thedistal section (e.g., to increase the relative stiffness of the proximalsection). In some variations, the stiffness of the proximal section maybe at least about 20% greater (e.g., about 20% greater, about 30%greater, about 40% greater, about 50% greater, about 60% greater, about70% greater, about 80% greater, about 90% greater, about 100% greater,about 150% greater, or about 200% greater, or even more), than thestiffness of the distal section. Factors that may affect the relativestiffness of the proximal and distal sections include, for example, thegeometries of the sections, the material compositions of the sections,and the material hardnesses (durometers) of the sections.

As described above, the distal and proximal sections may be joined inany suitable manner. For example, as illustrated in FIG. 12, they may beintegral or may have a common wall (1257). Alternatively, the proximaland distal sections may be formed separately, and may later be joined byany suitable method (e.g., by fusing the two sections together, securingthe two sections to each other with an adhesive, or mechanicallycoupling the two sections to each other). In some variations, atransition section may be interposed between the proximal and distalsections.

The relative stiffness of the proximal section may be selected such thatinducing movement in the distal section by application of force on thetensioning element may not result in substantial corresponding movementin the proximal section. That is, the stiffness of the proximal sectionmay at least partially shield or decouple the proximal section frommovement in the distal section. As an example, in some variations, apoint on the flexible distal section may be translated and/or rotated bya distance of at least about 0.5 millimeter (e.g., about 0.5 millimeter,about 1 millimeter, about 2 millimeters, about 3 millimeters, about 4millimeters, about 5 millimeters, about 6 millimeters, about 7millimeters, about 8 millimeters, about 9 millimeters, or about 1centimeter, or even farther), without any detectable motion in theproximal section.

Referring now to FIGS. 13A-13C, any of a variety of different tensioningelements (e.g., having different lengths and/or made of differentmaterials) may be used in the devices described herein. For example,FIG. 13A shows a catheter (1301 a) comprising an ultrasonic transducer(1344 a) and a tensioning element (1348 a) in the form of a wire ortendon (e.g., a flexor tendon, such as a polymeric cable). In somevariations, tensioning element (1348 a) may comprise a stiff wire ortendon that can support force applied in both distal and proximaldirections, to thereby steer the distal section (1356 a) of catheter(1301 a). This, in turn, may provide control over the positioning ofultrasonic transducer (1344 a), which is located in distal section (1356a). In other variations, tensioning element (1348 a) may primarilysupport only force applied in a proximal direction, and the resiliencyof the flexible distal section (1356 a) may function to pull the distalsection in a distal direction when proximal force on tensioning element(1348 a) is released or reduced.

As shown in FIG. 13B and as discussed briefly above, in some variations,a catheter may comprise more than one tensioning element. For example,FIG. 13B shows a catheter (1301 b) that, in addition to comprising anultrasonic transducer (1344 b), comprises multiple tensioning elements(1348 b′) and (1348 b″) arranged around the circumference of catheter(1301 b). The tensioning elements may be arranged in any suitableconfiguration (e.g., at positions that are about 180° apart from eachother, or that are about 90° apart from each other). The tensioningelements may or may not be uniformly distributed around the catheter.The multiple tensioning elements may be secured to the distal section(1356 b) of catheter (1301 b) at positions (1354 b′) and (1354 b″) thatare approximately equidistant from the catheter's distal end (1364 b).Alternatively, the multiple tensioning elements may be secured atpositions that are not equidistant from the distal end. In some of thesevariations, the tensioning elements may comprise one or more materialsthat are capable of supporting force primarily in a proximal directiononly (e.g., a flexible wire, cable or suture made of polymer or metal,etc.). In such variations, the resiliency of the distal section mayapply an opposing force, thereby causing the distal section to movedistally when a proximal force on one or more tensioning elements isreduced or released. In still other variations, the tensioning elementsmay be in the form of relatively stiff wires or tendons capable ofsupporting force in both distal and proximal directions. Force may beapplied to the tensioning element(s) separately or simultaneously, toenable steering of distal section (1356 b).

In still other variations, and as illustrated in FIG. 13C, a catheter(1301 c) may include a tensioning element (1348 c) and pulleys (1362 c).While two pulleys are shown, one pulley or more than two pulleys may beused in some variations, as appropriate. As shown, the tensioningelement may be wound around the pulleys, which may be attached to thedistal section (1356 c) of catheter (1301 c) (e.g., at a position (1354c)). Opposite forces (indicated by arrows) may be applied to oppositeends of a cord (1363 c) (e.g., a polymeric or metal suture, or aflexible metal wire) that is wound around pulleys (1362 c), to allowsteering of the distal section of the catheter. As shown, the distalsection of the catheter incorporates at least one ultrasonic transducer(1344 c), such that the catheter may be used, for example, to visualizeits own positioning, and/or the positioning of one or more otherdevices, at a target site. While pulleys are shown, in some variations,one or more pulley-like structures or arrangements may alternatively oradditionally be used. Moreover, in certain variations, only one pulleymay be used, or more than two pulleys may be used.

FIG. 4, previously discussed above, illustrates another variation of asuitable catheter that may be used with one or more of the methodsdescribed herein. As shown there, catheter (401) comprises a proximalsection (440) joined to a distal section (456), as well as two lumens(468) and (469). Both lumens may pass through at least a portion of eachof the proximal and distal sections of the catheter. Additionally, invariations in which the catheter includes a transition section betweenthe proximal and distal sections, both lumens will pass through thetransition section. As shown in FIG. 4, the lumens may have a commonwall (471). Catheter (401) also comprises a tensioning element (448)threaded through the first lumen (468) and secured to distal section(456) at a position (454) proximate a window region (450). The securingposition (454) for tensioning element (448) may be located at anysuitable position relative to window region (450) (e.g., proximal to,distal to, or within the window region). Any appropriate tensioningelements may be used, such as a flexor tendon or one or more of thetensioning elements illustrated in FIGS. 13A-13C.

Still referring to FIG. 4, catheter (401) further comprises anultrasonic transducer (444) and a corresponding connector (446). Secondlumen (469), which houses connector (446), may be open to the interior(470) of window region (450), which houses ultrasonic transducer (444).In some variations, the inner diameter of second lumen (469) may belarge enough to accommodate rotation of ultrasonic transducer (444).Moreover, the interior wall surface of second lumen (469) may be linedor coated with one or more lubricious substances (e.g., high-densitypolyethylene (HDPE) or polytetrafluoroethylene (PTFE)), which may allowconnector (446) and/or ultrasonic transducer (444) to rotate and/ortranslate in a low-friction environment within the lumen.

FIG. 14 shows another example of a steerable catheter (1401) that may beused, for example, to view the subannular groove of a heart, anatomynear the subannular groove, and/or implants in and/or near thesubannular groove. As shown in FIG. 14, catheter (1401) comprises aproximal section (1440) joined to a distal section (1456) comprising awindow region (1450) and a distal tip (1452). At least one ultrasonictransducer (1444) is housed within window region (1450). Ultrasonictransducer (1444) is connected to a connector (1446) extendingproximally through the catheter to a first branch (1474) of the proximalend (1473) of the catheter. Catheter (1401) also comprises a tensioningelement (1499) extending from a securing point (1454) in distal section(1456) to a second branch (1475) of proximal end (1473).

First branch (1474) of proximal end (1473) may be interfaced with acontroller (1476) that controls ultrasonic transducer (1444). Controller(1476) may rotate and/or translate ultrasonic transducer (1444) viaconnector (1446), for example. In some variations, controller (1476) mayalso transmit signals to, or receive signals from, ultrasonic transducer(1444) via connector (1446). Controller (1476) may in turn be interfacedwith a signal processor, microprocessor and display unit to analyze andprepare images from the signals received from the transducer and todisplay those images to a user (e.g., a medical professional oroperator). Second branch (1475) of proximal end (1473) is interfacedwith a user control (1477) that allows the user to steer distal section(1456) of catheter (1401) by applying force to, or releasing force from,tensioning element (1499). The user control (1477) may comprise a lever,a knob, a handle, or the like.

Still referring to FIG. 14, catheter (1401) in this variation comprisestwo lumens (1468) and (1469). The first lumen (1469) is open to theinterior (1470) of the window region housing transducer (1444), andextends continuously from the interior (1470) of the window region toproximal end (1473) of catheter (1401). The second lumen (1468) housestensioning element (1499). Second lumen (1468) may extend distally tojust proximal of the window region (1450) or, as illustrated here, mayterminate at a position (1478) more proximal to the window region.Additionally, second lumen (1468) may extend proximally to the proximalend (1473) or, as illustrated here, may terminate at a point (1479) thatis distal to the proximal end. The proximal section (1440) of catheter(1401) may be reinforced (e.g., with a reinforcing layer (1458)) so thatit is stiffer and/or harder than the distal section (1456). Areinforcing layer may be disposed on the exterior surface of thecatheter wall, as illustrated here in FIG. 14, or on the interiorsurface of the catheter wall. In some variations, the catheter wallitself may be reinforced, for example by using embedded mesh, fibers,fillers, combinations thereof, or the like.

In certain variations, first lumen (1469) may be at least partiallylined with a lubricious sheath or coating (1480). The lubricious sheathor coating may be made of any suitable material, such as high-densitypolyethylene (HDPE) or polytetrafluoroethylene (PTFE), and may provide alow-friction environment in which connector (1446) may rotate and/ortranslate relatively easily. In some variations, the lubricious sheathor coating may extend along the entire length of the catheter, while inother variations, the lubricious sheath or coating may extend along onlya portion of the catheter. For example, in the variation shown,lubricious sheath or coating (1480) extends distally from the firstbranch (1474) of the proximal end (1473) a point (1481) that is proximalto the window region (1450).

As described previously, the proximal section of the catheter may bestiffer or harder than the distal section. This may, for example, helpto shield the proximal section from movement in the more flexible distalsection. In some variations, the relative stiffness or hardness of theproximal section may be provided by, for example, increasing thecatheter wall thickness in the proximal section, forming the proximalsection of one or more stiffer or harder materials than the distalsection, and/or applying one or more reinforcing structures (e.g., wovenor braided meshes, ribs and/or spines) to an exterior surface of thecatheter wall, an interior surface of the catheter wall, and/or the bulkof the catheter wall. In certain variations, a combination of featuresmay be used to achieve relative stiffness in a proximal section. In somevariations of catheters including two lumens, it may be desirable toreinforce only the walls of one of the lumens in the proximal section ofthe catheter. For example, with respect to catheter (401) depicted inFIG. 4, only the walls of the lumen (469) housing the transducer (444)have been reinforced with an inner braided wall (458).

Some variations of the catheters described here may have an extendedwindow region. For example, a substantial portion of the flexible distalsection of a catheter may be at least partially transparent toultrasonic energy. By a “substantial portion of the distal section,” itis meant that the surface area of the window region (i.e., a region thatis at least partially transparent to ultrasonic energy) comprises atleast about 10% (e.g., at least about 15%, at least about 25%, at leastabout 35%, at least about 45%, at least about 55%, at least about 65%,at least about 75%, at least about 85%, or at least about 95%) of thesurface area of the flexible distal section.

FIG. 15 shows a catheter (1501) comprising a distal section (1556)having a window region (W_(R)) extending from the distal boundary of theproximal stiff section (1540) of the catheter to the catheter distal tip(1552). The walls (1530) of the extended window region are at leastpartially transparent to ultrasonic energy. For example, walls (1530)may be made of a thin polymer film having a thickness of about 0.007inch or less (e.g., about 0.006 inch, about 0.005 inch, about 0.004inch, about 0.003 inch, or about 0.002 inch). In some variations, thewalls may be formed of one or more polymers, such as nylon, PEBAX®polymer, polyethylene, and/or polyimide. Other suitable materials mayalso be used. The distal section has a radius of curvature that may bereduced by applying force in a proximal direction via a tensioningelement (not shown). Catheter (1501) comprises an ultrasonic transducer(1544) that may be translated along the extended window region (W_(R))by translation of a connector (1546). Ultrasonic transducer (1544) mayenable ultrasonic visualization of anatomy and/or structures, such asthe subannular groove, the mitral valve, and/or implants in or near thesubannular groove or the mitral valve. Of course, transducer (1544) mayalso be rotated using connector (1546).

As discussed above, some catheters may be at least partially radiopaque.For example, a catheter may comprise a wall made from a polymercomposite comprising one or more radiopaque materials, such as bariumsulfate or bismuth trioxide, and/or metal markers (e.g., tungstenmarkers). Catheters may also be at least partially coated with one ormore radiopaque materials. For example, select portions of a cathetermay be at least partially coated (e.g., by plating or sputtering) with abiocompatible metal such as gold, silver, titanium, tantalum, or alloysthereof, or coated with a polymer or ink that contains a radiopaquematerial (e.g., metal markers such as tungsten markers, or bariumsulfate or bismuth trioxide). In some variations, catheters may berendered radiopaque using a polymer with chemically bound radiopaquemoieties (e.g., iodine-containing moieties). Catheters that are at leastpartially radiopaque may be used in methods that combine ultrasonicvisualization techniques with fluoroscopic visualization techniques,such as those described earlier, wherein a contrast agent is injectedinto the subannular groove to visualize the subannular groove.

While certain variations of devices have been described, additionalvariations of visualization devices may be used. In some variations, avisualization device may comprise at least one scope. The scope(s) maybe used, for example, to locate a target site for implant (e.g., anchor)deployment, and/or to evaluate an implant and/or a target site after theimplant has been deployed at the target site. In certain variations inwhich a visualization device comprising a scope is used in a cardiacprocedure (e.g., a heart valve repair procedure), the scope may be usedto locate and evaluate an annulus, leaflets, and/or commissures of theheart. A scope may also be used to help an operator become oriented asto the environment of a target site, to observe implant deploymentand/or orientation during and/or after a procedure, and/or to assess animplant after it has been deployed into tissue. For example, a scope maybe used to determine whether a deployed anchor is positioned correctly,or whether an anchor's arms have bent or curved sufficiently upondeployment. A scope may also be used to observe the state of a tethercoupling multiple anchors to each other (e.g., whether the tether isdamaged), or may be used for any other suitable purpose.

In some variations, a visualization device may comprise a scope, such asa fiber optic scope or a rigid scope, that may be at least partiallypositioned within a scope housing during use. The scope housing may, forexample, help to protect the scope during use, and/or may help to limitthe likelihood of the scope causing damage to tissue as the scope isadvanced to a target site, or once the scope has reached the targetsite. Additionally, the scope housing may enhance the scope'svisualization of the surrounding area. Housings may have any appropriatesize and shape. Furthermore, in variations employing multiple scopes,each scope may be disposed within its own individual housing, or atleast two scopes may share a housing.

In certain variations, a scope housing may be bubble-shaped. The roundedshape of a bubble housing may, for example, make the housing relativelyatraumatic toward tissue, and may also allow for good visualization oftissue surrounding the housing. For example, FIG. 50 shows avisualization device (5000) comprising a housing (5001) including afirst outer wall portion (5002) and a second inner wall portion (5004)defining two lumens (5008) and (5010) therebetween. Device (5000) alsocomprises a scope (5016) located within lumen (5008), as well as ananchor (5018) located within lumen (5010).

In some variations, wall portions (5002) and (5004) may be formed of oneor more relatively transparent materials. Non-limiting examples of suchmaterials include polymers, such as polyether-block co-polyamidepolymers (e.g., PEBAX® polyether block amide copolymers, including butnot limited to PEBAX® 35D polymer, PEBAX® 40D polymer, PEBAX® 55Dpolymer, PEBAX® 63D polymer, and PEBAX® 72D polymer), copolyesterelastomers, thermoset polymers, polyolefins (e.g., polypropylene orpolyethylene, including high-density polyethylene (HDPE) and low-densitypolyethylene (LDPE)), ethylene vinyl acetate copolymers, polyamides,polyimides, polyurethanes (e.g., POLYBLEND™ polymer), polyvinyl chloride(PVC), fluoropolymers (e.g., fluorinated ethylene propylene (FEP),perfluoroalkoxy (PFA) polymer, polyvinylidenefluoride (PVDF), etc.),silicones, and copolymers and combinations (e.g., blends) thereof.Examples of polyamides include nylon 6 (e.g., ZYTEL® HTN highperformance polyamides from DuPont™), nylon 11 (e.g., RILSAN® Bpolyamides from Arkema Inc.), and nylon 12 (e.g., GRILAMID® polyamidesfrom EMS-Grivory, RILSAN® A polyamides from Arkema Inc., and VESTAMID®polyamides from Degussa Corp.). Other polymers and/or non-polymericmaterials may also be used. Moreover, in certain variations, one or morematerials (e.g., polymers) may be combined (e.g., blended), if it issuitable to do so.

Using one or more relatively transparent materials in wall portions(5002) and (5004) may, for example, allow for scope (5016) to achieverelatively good visualization of the tissue surrounding device (5000),and/or may allow for an operator to determine the location of scope(5016) and/or anchor (5018) relatively easily.

As shown, device (5000) further includes a rounded dome- orbubble-shaped scope housing (5012) in its distal portion (5014),extending from wall portions (5002) and (5004). Scope (5016) partiallyextends into scope housing (5012), and may in some cases be translatableso that the scope may be further extended into the scope housing, or maybe retracted from the scope housing.

Scope (5016) is angled at its distal end (5020), so that it may providean angled line of sight through scope housing (5012). More specifically,the distal edge (5021) of scope (5016) forms an angle (α48) relative tothe longitudinal axis (LA1) of scope (5016). Angle (α48) may be, forexample, from about 25° to about 85° (e.g., from about 30° to about60°). Of course, scope (5016) is only one variation of a scope, andother variations may alternatively or additionally be used with any ofthe devices described here, as appropriate.

Anchor (5018) comprises an elongated member (5022) and a distalanchoring portion (5024), which is sized and shaped to temporarilyanchor into tissue. Distal anchoring portion (5024) is depicted ashaving a single tissue-piercing tip. However, other variations ofdevices may use anchoring portions having different configurations, asappropriate. As an example, in some variations, an anchoring portion maycomprise multiple tissue-piercing tips. Anchor (5018) may be used, forexample, to help stabilize device (5000) while the device is used tovisualize a target site.

During use, device (5000) may be advanced toward a target site. Scope(5016) may be actuated prior to, during, and/or after such advancement,to provide a view of the pathway to the target site, and/or to provide aview of the target site itself. Scope housing (5012) may shield scope(5016), so that the scope does not damage tissue (e.g., by snagging thetissue), and so that the scope is less likely to experience any damageitself. In some cases, distal anchoring portion (5024) of anchor (5018)may be temporarily anchored into tissue when device (5000) is in use.This temporary anchoring may, for example, help to stabilize device(5000) with respect to the tissue, allowing the scope to provide areliable image of its surroundings. In certain variations, anchor (5018)may be deployable from, and retractable into, lumen (5010). This may,for example, allow the distal anchoring portion (5024) to be extendedwhen desired for use, and to otherwise be retracted (e.g., to limit thelikelihood of harm to tissue when the distal anchoring portion is not inuse). While a visualization device comprising one anchor has beendescribed, it should be noted that some variations of visualizationdevices comprising one or more scopes may comprise more than one anchor,or may not comprise any anchors at all.

As discussed above, other variations of anchors may be used. The type ofanchor that is used in a device may depend, for example, on the natureof the target tissue and/or the desired anchoring time and stability.FIG. 51 shows another variation of a visualization device (5100)comprising an anchor having a different configuration from anchor (5018)above. More specifically, device (5100) comprises a housing (5102)including a first wall portion (5104) and a second wall portion (5106)defining two lumens (5110) and (5112) therebetween. As shown, device(5100) further includes a rounded dome or bubble (5114) in its distalportion (5116), extending from wall portions (5104) and (5106).Additionally, device (5100) comprises a scope (5118) located withinlumen (5110), as well as an anchor (5120) located within lumen (5112).

Anchor (5120) comprises an elongated member (5122) and a distalanchoring portion (5124), which is sized and shaped to temporarilyanchor into tissue. As shown, a portion (5126) of elongated member(5122) is disposed within lumen (5112), while another portion (5128) ofelongated member (5122) is disposed within a funnel-shaped housing(5130) extending from the distal end (5132) of housing (5102), betweenwall portions (5106) and (5104). Distal anchoring portion (5124) extendsdistally beyond the distal end (5134) of funnel-shaped housing (5130).Funnel-shaped housing (5130) may be formed of any appropriate materialor materials, and in some variations, may be formed of one or morerelatively transparent materials, such as one or more of the materialsdescribed above with reference to wall portions (5002) and (5004) inFIG. 50. Funnel-shaped housing (5130) may be sized and shaped totemporarily seal against tissue during use. This may, for example, helpto provide a more stable anchoring of distal anchoring portion (5124)into tissue. While housing (5130) is funnel-shaped, any other shapesthat are suitable for achieving a similar effect may be used. Inaddition, in certain variations, saline may be flushed through lumen(5112) and into funnel-shaped housing (5130) during use (e.g., to keeplumen (5112) clear and the visualization zone blood-free).

While devices having bubble-shaped scope housings have been described,some variations of devices may comprise scope housings having differentshapes or configurations. The size and shape of a scope housing maydepend, for example, on the size and shape of the scope being housed(which, in turn, may depend on the characteristics of the targetanatomy, such as the size of an atrial opening of a heart, and/or on oneor more other factors).

Some variations of devices may have other configurations suitable forpositioning and/or stabilizing the device and/or an anchor of the deviceduring use. For example, FIG. 52 shows an exemplary visualization device(5200) comprising an outer tubular member (5202) and an inner tubularmember (5204) disposed within a lumen (5206) of outer tubular member(5202). Inner tubular member (5204) also has its own lumen (5208). Asshown, device (5200) further includes a donut-shaped balloon (5210) atthe distal end (5212) of outer tubular member (5202). While balloon(5210) has a small opening (5214) at its center, the opening iseffectively sealed together by its various sides contacting each other.As a result, balloon (5210) effectively seals lumen (5208) of innertubular member (5204). Device (5200) also comprises a scope (5216)located within lumen (5206), as well as an anchor (5218) located withinlumen (5208). Anchor (5218) comprises an elongated member (5220) and adistal anchoring portion (5222), which is sized and shaped totemporarily anchor into tissue.

During use, balloon (5210) may be positioned against tissue, and anchor(5218) may be pushed through opening (5214) so that distal anchoringportion (5222) may contact and anchor into the target tissue. Anchor(5218) may be extendible and/or retractable in order to achieve thisanchoring. Alternatively or additionally, device (5200) may be capableof allowing distal anchoring portion (5222) to be extended and/orretracted independently of the rest of anchor (5218), so that distalanchoring portion (5222) may push through opening (5214) and intotissue. The presence of balloon (5210) causes anchor (5218) to assume avery specific and intended positioning during use. This may help tolimit the likelihood of the anchor damaging target tissue, and may alsoresult in highly targeted and controlled deployment of the anchor.

In some variations, a visualization device may comprise one or morerotatable components. As an example, a visualization device may compriseat least one rotatable scope. In some such variations, the operator maybe capable of controlling scope rotation using one or more actuators(e.g., located in a proximal portion of the device). FIGS. 53A-53Dprovide illustrative cross-sectional views of different variations ofvisualization devices comprising rotatable scopes. While rotatablescopes are depicted, it should be understood that certain variations ofvisualization devices may alternatively or additionally comprise one ormore other rotatable components, such as rotatable scope housings.

Referring specifically now to FIG. 53A, a visualization device (5300)comprises an outer tubular member (5302) and an inner tubular member(5304) disposed within a lumen (5306) of the outer tubular member.Device (5300) further comprises a scope (5308) located within lumen(5306), as well as an anchor (5310) located within a lumen (5312) ofinner tubular member (5304). As shown, scope (5308) is capable ofrotating within lumen (5306), around inner tubular member (5304), in thedirection of arrow (5314) or arrow (5316). Scope (5308) is notrestricted in its rotation—in other words, it is capable of rotatingaround the entirety of inner tubular member (5304). Such rotatabilitymay, for example, allow for a very comprehensive view of the targetsite.

FIG. 53B shows another variation of a visualization device (5320)comprising a scope that, while rotatable, is restricted somewhat in itsrotation. As shown there, device (5320) comprises an outer scope housing(5322) surrounding an inner tubular member (5324). Device (5320) furthercomprises a scope (5326) disposed within outer scope housing (5322), andan anchor (5328) disposed within a lumen (5330) of inner tubular member(5324). Scope (5326) is rotatable within outer scope housing (5322), inthe direction of arrow (5332) or arrow (5334). However, outer scopehousing (5322) comprises two wall portions (5336) and (5338) thatprevent scope (5326) from fully rotating around inner tubular member(5324).

While FIGS. 53A and 53B depict devices comprising centrally locatedanchors and anchor housings, anchors and anchor housings may bepositioned in any appropriate location of a visualization device. Forexample, FIG. 53C shows a visualization device (5340) comprising anouter tubular member (5342) and an inner tubular member (5344) disposedwithin a lumen (5346) of the outer tubular member. Device (5340) alsocomprises a scope housing (5348) disposed within lumen (5346) of outertubular member (5342), as well as a rotatable scope (5350) disposedwithin scope housing (5348). Additionally, device (5340) comprises ananchor (5352) disposed within inner tubular member (5344). During use,scope (5350) may rotate within scope housing (5348) in the direction ofarrow (5354) or arrow (5356). However, the rotation of scope (5350) islimited by the boundaries of the scope housing. Moreover, given thislimitation, as well as the location of inner tubular member (5344) andanchor (5352), scope (5350) is not capable of completing a full 360°rotation within device (5340) (which is also the case with scope (5326)in FIG. 53B above).

FIG. 53D shows an additional variation of a visualization device (5360).As shown there, device (5360) comprises a tubular member (5362)comprising an outer wall portion (5363) and an inner wall portion (5364)that effectively divides tubular member (5362) into two portions (5366)and (5368). Portions (5366) and (5368) each have their own lumen (5370)and (5372), respectively. Device (5360) also comprises a scope (5374)disposed within lumen (5370), and an anchor (5376) disposed within lumen(5372). As shown in FIG. 53D, scope (5374) is capable of rotating withinlumen (5370), in the direction of arrow (5378) or arrow (5380). Whilescope (5374) is not capable of completing a full (360°) rotation withinlumen (5370), some variations of visualization devices may comprise oneor more scopes that are capable of such rotation within a lumen of aportion of the device.

In certain variations, a visualization device may comprise multiple(e.g., two, three, four, five, etc.) scopes. In a device comprisingmultiple scopes, the scopes may all be the same as each other, or atleast two of the scopes may be different from each other (e.g., in size,shape, type of scope, etc.). Moreover, each scope may be positioned inits own housing, or at least two scopes may be positioned in the samehousing. Additionally, the scopes may be positioned for visualization ofdifferent regions of a target site, and in some cases, may beindividually actuated (e.g., so that the desired image or images may beachieved by actuating selected scopes).

An exemplary variation of a visualization device comprising multiplescopes is depicted in FIGS. 54A and 54B. As shown there, a visualizationdevice (5400) comprises a tubular member (5402) comprising an outer wallportion (5403) and two inner wall portions (5404) and (5406). Inner wallportions (5404) and (5406) partition outer tubular member (5402) so thatdevice (5400) has three lumens (5408), (5410) and (5412). Device (5400)further comprises a first scope (5414) disposed within lumen (5408), anda second scope (5416) disposed within lumen (5412). Scope (5414) is alsopartially disposed within a rounded dome- or bubble-shaped scope housing(5418) that is located in a distal portion (5420) of device (5400), andthat is in fluid communication with lumen (5408). Similarly, scope(5416) is partially disposed within a rounded dome- or bubble-shapedhousing (5422) that is also located in distal portion (5420) of device(5400), but that is in fluid communication with lumen (5412).

Device (5400) further comprises an anchor (5424) disposed within lumen(5410), where the anchor comprises an elongated member (5426) and adistal anchoring portion (5428). As shown in FIG. 54A, a portion (5430)of elongated member (5426) is disposed within lumen (5410), whileanother portion (5432) of elongated member (5426) is disposed within afunnel-shaped housing (5434) extending from inner wall portions (5404)and (5406). Distal anchoring portion (5428) extends distally beyond thedistal end (5436) of funnel-shaped housing (5434). In some cases, and asdiscussed with respect to funnel-shaped housing (5130) above,funnel-shaped housing (5434) may be sized and shaped to temporarily sealagainst tissue during use. This may, for example, help to provide a morestable anchoring of distal anchoring portion (5428) into tissue.

Of course, device (5400) is only one variation of a visualization devicecomprising multiple scopes, and other variations (e.g., having differentconfigurations) may be used, as appropriate. For example, FIG. 55depicts a variation of a visualization device (5500) comprising atubular member (5502) and multiple fiber scopes (5504) embedded within awall portion (5506) of the tubular member. Device (5500) furthercomprises an anchor (5508) disposed within a lumen (5510) of tubularmember (5502). As shown, scopes (5504) are essentially evenlydistributed radially around tubular member (5502). However, othervariations of visualization devices may comprise scopes that are notevenly distributed or positioned, and/or that form different patterns.The arrangement of scopes in a device may be selected, for example,based on the target site and the desired image or images to be obtainedtherefrom.

Still other variations of visualization devices employing scopes may beused. For example, FIG. 56A shows a visualization catheter (5600)comprising a flexible tubular member (5602) including a wall portion(5604) and having a lumen (5606) therethrough. Catheter (5600) alsocomprises a transparent balloon (5608) at the distal end (5610) oftubular member (5602). In some cases, balloon (5608) may be inflatedand/or deflated as desired, or may be capable of a one-time inflationand/or a one-time deflation. During use, and as shown in FIG. 56A, along flexible endoscope (5612) may be passed through lumen (5606) oftubular member (5602), sliding axially within the tubular member. Adistal portion (5614) of the endoscope may be positioned within balloon(5608), as depicted. The endoscope may then be used to view thesurrounding area. Endoscope (5612) may, for example, have a length ofabout 10 centimeters to about 150 centimeters, and/or a diameter ofabout 1 millimeter to about 3 millimeters. The size of endoscope (5612)and/or catheter (5600) may depend, for example, on the characteristicsof the target site.

In some variations, catheter (5600) may be advanced to a target site bybeing passed within another catheter, such as a guide catheter or atunnel catheter. For example, FIG. 56B depicts catheter (5600) disposedwithin a lumen (5616) of a guide catheter (5618). With distal end (5614)of endoscope (5612) positioned within balloon (5608), catheter (5600)may then be positioned so that balloon (5608) is located at the distalend of the catheter in which catheter (5600) is disposed. In somevariations, balloon (5608) may be in a deflated form as catheter (5600)is being positioned, and may later be inflated (e.g., with saline or asaline-contrast solution). The inflation of balloon (5608) may displaceblood surrounding distal end (5614) of endoscope (5612). This blooddisplacement, in turn, may allow the space occupied by optically clearballoon (5608) to be visualized. By being able to visualize the spacejust distal to the distal end or tip of the guide catheter, tunnelcatheter, or other catheter or device in which catheter (5600) ispositioned, the operator may be able to navigate the catheter or devicesuccessfully to the target site (e.g., the subannular space).

As discussed above, balloon (5608) is optically transparent or clear.Balloon (5608) may comprise one or more materials, such as one or morepolymers. Non-limiting examples of polymers which may be appropriateinclude polyurethanes, nylon, polyesters (e.g., polyethyleneterephthalate or PET), neoprene, silicone, and polyethylene.Combinations (e.g., blends) of polymers and/or other materials may alsobe used. In certain variations, balloon (5608) may comprise latex. Insome variations, balloon (5608) may comprise isoprene. Balloon (5608)may be relatively elastic, and in use may conform to surroundinganatomical structures, such as the ventricular wall, chordae tendineae,and/or heart valve leaflets. This conformational characteristic of theballoon surface may enhance the ability of balloon (5608) to displaceblood surrounding anatomical structures, so that catheter (5600) may beused to provide relatively high optical visibility of the anatomicalstructures.

Catheter (5600) (e.g., tubular member (5602)) may comprise one or morematerials. Exemplary materials include polymers, such as nylon,polyurethane, PEBAX® polyether block amide copolymers, polyolefins(e.g., polyethylene), polyetheretherketone (PEEK), polyimides, andfluoropolymers. Combinations of polymers and/or other materials may alsobe used. For example, in some variations, catheter (5600) may comprise ametal wire braid or coil disposed within a polymer matrix.

In certain variations, a catheter comprising at least one scope may alsocomprise a tendon or other tensioning member that may be tensioned tomaneuver the catheter. For example, FIG. 57 depicts a visualizationcatheter (5700) comprising a flexible elongated member (5702) includingfirst and second wall portions (5704) and (5705), as well as first andsecond lumens (5706) and (5707). Catheter (5700) also comprises atransparent balloon (5708) at the distal end (5710) of elongated member(5702), which is in fluid communication with second lumen (5707).Catheter (5700) further comprises a tensioning member (5712) disposedwithin first lumen (5706), where the tensioning member is configured tobe tensioned in the direction of arrow (5714), to flex elongated member(5702). As shown, a long flexible endoscope (5716) may be passed throughsecond lumen (5707), and its distal portion (5718) may be positionedwithin balloon (5708). While catheter (5700) is depicted as comprisingone tensioning member (5712), other variations of catheters may comprisemultiple (i.e., at least two) tensioning members. The tensioning membersmay all be disposed within a single lumen of the catheter, or at leasttwo tensioning members may be disposed in different lumens of thecatheter. Moreover, in some variations, a visualization catheter maycomprise at least one tensioning member that is not disposed within anylumens of the catheter.

As described above, in certain variations, a visualization device and/ormethod may be used in conjunction with a chord manipulation catheter,diagnostic catheter and/or guide catheter. Moreover, a visualizationdevice and/or method may be used in conjunction with any otherappropriate catheter. Furthermore, in some variations, a chordmanipulation catheter, diagnostic catheter and/or guide catheter mayalso be capable of functioning as a visualization catheter. Of course,in certain variations, a chord manipulation catheter, diagnosticcatheter and/or guide catheter may be used independently of any of thevisualization devices and/or methods described here.

Catheter Configurations

In some variations, a catheter, such as a diagnostic catheter, chordmanipulation catheter, guide catheter or visualization catheter, maycomprise one or more curve regions. The curve regions may, for example,help the catheter to be successfully navigated to, and/or positionedwithin, a target site. In certain variations, the curvature of acatheter may be designed to cause the catheter to automatically registerwith the subannular groove region of a heart, and/or to automaticallycannulate the subannular groove. This may, for example, allow for highlypredictable and accurate positioning of the catheter within thesubannular groove region of the heart. Additionally, it may berelatively easy for an operator to accurately deliver such a catheter toa subannular groove region of a heart.

An exemplary curved catheter is shown in FIGS. 16A-16D. As shown there,a guide catheter (1650) comprises a proximal operating portion (1652)and a shaft (1670) (e.g., which may be braided) comprising a distalportion (1672) having a compound curve (1673). Compound curve (1673) maybe used, for example, to help access a target site, such as a subannulargroove of a heart. For example, the compound curve may be configured toallow the catheter to automatically register in the subannular groove.Proximal operating portion (1652) includes a hemostatic valve (1654), aport (1656), a hub cap (1658), and a pullwire tensioning knob (1660). Apullwire (1674) is connected to pullwire tensioning knob (1660), andextends through shaft (1670) to distal portion (1672), where thepullwire is connected to a pullwire ring (1676). Pullwire (1674) may beused to deflect a deflectable section (1678) of distal portion (1672).As shown in FIG. 16D, guide catheter (1650) also comprises an atraumaticor soft tip (1680). While guide catheter (1650) includes curves and adeflectable section, some variations of guide catheters or other typesof catheters may include one or more curves without including anydeflectable sections. Additionally, certain variations of catheters maycomprise a deflectable section that may be deflected into a curvedshape, but may not comprise any other curve regions.

While a curved guide catheter has been described, other types ofcatheters may also have one or more curve regions. Moreover, it shouldbe understood that curve regions and features discussed herein withrespect to one type of catheter may be applied to other types ofcatheters, as appropriate. FIG. 16E shows a portion of a diagnosticcatheter (1600) having three curve regions: a valve curve region (1602),a transition curve region (1604), and an arch curve region (1606). Thegeometry of diagnostic catheter (1600) may, for example, allow specificanatomical landmarks to be targeted during use. The geometry of acatheter such as diagnostic catheter (1600) may also allow for automaticpositioning of the catheter at a target site, such as automaticcannulation of the subannular groove. Each of the curve regions will nowbe discussed in further detail below.

Arch curve region (1606) typically may be sized and shaped to fit within(e.g., to conform to the curve of) the aortic arch of a heart. Thegeometry of arch curve region (1606) may cause diagnostic catheter(1600) to automatically orient toward the endocardial surface and awayfrom the center of the ventricular cavity during use. In somevariations, arch curve region (1606) may form an arc having an arcdiameter of about 3.5 inches to about 5 inches (e.g., about 4 inches)and/or defining a central angle of about 60° to about 2700 (e.g., about60° to about 180°, or about 100° to about 170°, such as about 150°).

Transition curve region (1604) generally may be sized and shaped forpositioning the distal portion (1608) of catheter (1600) (includingdistal end (1610)) within the mitral valve region. Transition curveregion (1604) typically may be shaped such that when diagnostic catheter(1600) has been delivered to a target subvalvular space of a heart,transition curve region (1604) spans from the aortic root to theentrance of the subannular groove, pointing toward the anterior side ofthe left ventricle. The diameter of the arc of transition curve region(1604) may be selected so that diagnostic catheter (1600) presses upagainst the septal wall of the heart when distal portion (1608) ofdiagnostic catheter (1600) is positioned in a subannular groove regionof a mitral valve. In certain variations, transition curve region (1604)may form an arc having an arc diameter of about 1 inch to about 3 inches(e.g., about 1 inch to about 2 inches, such as about 1.2 inches) and/ordefining a central angle of about 90° to about 2700 (e.g., about 120° toabout 270°, about 180° to about 270°, about 200° to about 270°, or about220° to about 250°, such as about 230°).

Finally, valve curve region (1602) typically may be sized and shaped tofit within a subannular groove region of a mitral valve. In some cases,valve curve region (1602) may automatically conform to the shape of thesubannular groove region during positioning, without requiring anyadjustment thereafter. In certain variations, valve curve region (1602)may be positioned at an angle of about 45° with respect to transitioncurve region (1604). However, upon insertion of the guide tunnel, valvecurve region (1602) may become planar relative to the subannular grooveof the mitral valve. In some variations, the length (or arc length) ofvalve curve region (1602) may be selected such that when diagnosticcatheter (1600) is withdrawn, there is sufficient length at the distalportion (1608) of diagnostic catheter (1600) to force diagnosticcatheter (1600) up against the septal wall of the heart without distalportion (1608) dislodging from the subannular groove. In somevariations, valve curve region (1602) may form an arc having an arcdiameter of about 0.75 inch to about 1.5 inches (e.g., about 0.75 inchto about 1.2 inches, or about 0.9 inch) and/or defining a central angleof about 60° to about 80° (e.g., about 70° or about 77°), or about 75°to about 120° (e.g., about 1000 to about 120°, such as about 115°).

Diagnostic catheter (1600) has three curve regions. However, in certainvariations, a diagnostic catheter may have one or two curve regions, ormay have more than three curve regions (e.g., four, five, six, etc.). Asan example, in some variations, a diagnostic catheter may have atransition curve region and a valve curve region, but may not have anarch curve region. In some such variations, the diagnostic catheter maybe sufficiently flexible to be easily routed through the aortic arch,without being pre-curved to fit the aortic arch. As another example, incertain variations, a diagnostic catheter may have a valve curve region,a transition curve region, and an arch curve region such as thosedescribed above with reference to FIG. 16E, and may also have a fourthcurve region. The fourth curve region may, for example, serve to bracethe diagnostic catheter up against the septal wall of the left ventricleof the heart. In some variations, a guide catheter may include a fourthcurve region that may brace the guide catheter up against the septalwall of the left ventricle of a heart when the guide catheter is beingadvanced to a subvalvular space of the heart. This bracing may, forexample, help to prevent backward movement of the guide catheter whenanother device is being advanced through and out of the guide catheter.

While one variation of a diagnostic catheter is described with referenceto FIG. 16E, and additional variations of diagnostic catheters aredescribed below, it should be understood that the sizes and/or shapes(and/or other appropriate characteristics) of the diagnostic cathetersdescribed herein may be applied to guide catheters, as well, andvice-versa. For example, in some variations, a diagnostic catheter andguide catheter may have the same curves with the same shapes, with theguide catheter having scaled-up dimensions relative to the diagnosticcatheter. Thus, it should be understood that the descriptions hereinwith respect to diagnostic catheters may also be applied to guidecatheters or other types of catheters (e.g., chord manipulationcatheters, anchor deployment catheters) as appropriate, and vice versa.

FIG. 16E shows only one example of a diagnostic catheter variation.

However, any number of different variations may be used. For example,FIGS. 17A-17G depict another variation of a diagnostic catheter having adifferent curvature from the diagnostic catheter of FIG. 16E.

As shown in FIGS. 17A-17C, a diagnostic catheter (1700) comprises avalve curve region (1702), a transition curve region (1704), and an archcurve region (1706). Referring specifically to FIG. 17C, diagnosticcatheter (1700) also comprises a region (1708) that is proximal to valvecurve region (1702), transition curve region (1704), and arch curveregion (1706). Region (1708) has a length (L1) that may be, for example,from about 25 inches to about 40 inches (e.g., from about 30 inches toabout 40 inches, or from about 30 inches to about 35 inches, such as32.715 inches). A proximal portion (1710) of region (1708) has a length(L2) that may be, for example, from about 1 inch to about 4 inches(e.g., from about 2 inches to about 3 inches, such as 2.473 inches).Additionally, and referring still to FIG. 17C, arch curve region (1706)forms an arc having an arc diameter (AD1) that may be, for example, fromabout 3 inches to about 5 inches (e.g., from about 3.5 inches to about4.5 inches, such as 3.5 inches). The arc also defines a central angle(α1) that may be, for example, from about 60° to about 180° (e.g., fromabout 60° to about 160°, from about 100° to about 160°, or from about100° to about 1400, such as 120°).

Additionally, and referring now to FIG. 17D, diagnostic catheter (1700)comprises a tubular member (1712) having an outer diameter (OD1) and aninner diameter (ID1). In some variations, inner diameter (ID1) may befrom about 1.33 millimeters to about 3 millimeters. Alternatively oradditionally, outer diameter (OD1) may be from about 1.67 millimeters toabout 3.33 millimeters.

As will be explained in further detail below, in a diagnostic cathetercomprising a valve curve region, a transition curve region, and/or anarch curve region, each region may define a different plane. Forexample, FIG. 17E shows that arch curve region (1706) defines an archplane (1716), while transition curve region (1704) defines a transitionplane (1718). In certain variations, the angle (a2) between arch plane(1716) and transition plane (1718) may be from about 20° to about 60°(e.g., from about 30° to about 60°, or from about 40° to about 60°, suchas 50°).

As shown in FIG. 17F, transition curve region (1704) forms an arc havingan arc diameter (AD2) that may be, for example, from about 1 inch toabout 3 inches (e.g., from about 1 inch to about 2 inches, such as 1inch). The arc also defines a central angle (a3) that may be, forexample, from about 90° to about 270° (e.g., from about 120° to about270°, from about 180° to about 270°, or from about 200° to about 270°,such as 270°). Additionally, and referring now to FIG. 17G, valve curveregion (1702) forms an arc having an arc diameter (AD3) that may be, forexample, from about 0.75 inch to about 1.5 inches (e.g., from about 0.8inch to about 1.3 inches, or from about 0.8 inch to about 1.1 inches,such as 1 inch), and defining a central angle (α4) that may be, forexample, from about 60° to about 120° (e.g., from about 75° to about120°, from about 1000 to about 120°, or from about 75° to about 105°,such as 90°).

In some variations, a catheter such as a diagnostic catheter, chordmanipulation catheter, guide catheter, and/or visualization catheter,may have a high degree of flexion that allows a flexible distal sectionof the catheter to be formed into a tighter curve. This may, forexample, provide the catheter with enhanced ability to navigate and, insome cases, to visualize, complex spaces such as a subannular groove ofa mitral valve.

A variation of such a catheter with a high degree of flexion is shown inFIGS. 18A and 18B. FIG. 18A shows the catheter (1801), which comprises aproximal section (1840) and a distal section (1856) in a configurationhaving a high degree of flexion due to tension applied to a tensioningelement (not shown) in catheter (1801). FIG. 18B shows catheter (1801)in an extended configuration. When catheter (1801) is in an extendedconfiguration, at least a portion of proximal section (1840) may have aradius of curvature (R_(P)) of at most about 1.6 inches (e.g., about0.75 inch, about 0.8 inch, about 0.85 inch, about 0.9 inch, about 0.95inch, about 1.0 inch, about 1.05 inches, about 1.1 inches, about 1.15inches, about 1.2 inches, about 1.25 inches, about 1.3 inches, about1.35 inches, about 1.4 inches, about 1.45 inches, or about 1.5 inches).Alternatively or additionally, at least a portion of distal section(1856) may have a radius of curvature (R_(D)) of at most about 1.6inches (e.g., about 0.75 inch, about 0.8 inch, about 0.85 inch, about0.9 inch, about 0.95 inch, about 1.0 inch, about 1.05 inches, about 1.1inches, about 1.15 inches, about 1.2 inches, about 1.25 inches, about1.3 inches, about 1.35 inches, about 1.4 inches, about 1.45 inches, orabout 1.5 inches).

The curvature of distal section (1856) may define a plane that isdistinct from the plane defined by the curvature of proximal section(1840). In some variations, the planes may be oriented at about 90°relative to each other, while in other variations, the planes may beoriented at a different angle relative to each other (e.g., about 60° orabout 30° relative to each other). The relative orientation of theplanes may be selected, for example, based on the anatomy or structureto be visualized.

As shown in FIG. 18A, when catheter (1801) is flexed (e.g., to aconfiguration of maximum flexion by applying maximum tension to atensioning element of the catheter), the flexed portion of the catheterhas a dimension (D_(c)). In some variations, dimension (D_(c)) may befrom about 1.0 inch to about 1.5 inches (e.g., about 1.1 inches, about1.2 inches, about 1.3 inches, or about 1.4 inches).

As described above, a diagnostic catheter may comprise different regionshaving different curvatures. As another example of this type ofconfiguration, FIG. 19A shows a diagnostic catheter (1900) comprising avalve curve region (1902), a transition curve region (1904), and an archcurve region (1906). The curvature and size of each of these regions maydepend, for example, on the characteristics of the targeted anatomy. Forexample, FIG. 19B shows a diagnostic catheter (1950) being advanced intothe subvalvular space (1952) of a left ventricle (LV) of a heart (H),where the diagnostic catheter comprises a valve curve region (1954), atransition curve region (1956), and an arch curve region (1958). Thesethree curve regions are designed to correspond to the path that thecatheter takes to access subvalvular space (1952). Diagnostic catheter(1950) is configured such that, when disposed within the aortic arch(1960) of the heart, the diagnostic catheter has certain bracing points(1962) and (1966) that may help to stabilize its position. Of course,diagnostic catheter (1950) is only one variation of a diagnosticcatheter, and other variations of diagnostic catheters may includedifferent numbers or locations or bracing points, or may not include anybracing points.

As also described above, in a diagnostic catheter comprising a valvecurve region, a transition curve region, and/or an arch curve region,each region may define a different plane. For example, FIG. 20 shows adiagnostic catheter (2000) comprising a valve curve region (2002)defining a valve plane (2004), a transition curve region (2006) defininga transition plane (2008), and an arch curve region (2010) defining anarch plane (2012). In some cases, the relationships of two or more ofthese regions and/or planes to each other may be used to help define thecurved configuration of a diagnostic catheter (or any other appropriatecatheter). Additionally, while FIG. 20 shows a diagnostic catheterhaving three curve regions defining three different planes, diagnosticcatheters having different configurations may also be used. As anexample, a diagnostic catheter may comprise only two curve regionsdefining two different planes (e.g., a valve curve region defining avalve plane and a transition curve region defining a transition plane),or may comprise more than three curve regions defining more than threedifferent planes. As another example, in some variations, a diagnosticcatheter may comprise multiple curve regions, with at least two of thecurve regions defining different planes, and at least two of the curveregions defining the same plane.

FIGS. 21A-21C depict another variation of a diagnostic cathetercomprising three curve regions defining three planes. As shown there, adiagnostic catheter (2100) comprises a valve curve region (2102)defining a valve plane (2104), a transition curve region (2106) defininga transition plane (2108), and an arch curve region (2110) defining anarch plane (2112). Referring first to FIG. 21A, valve plane (2104) andtransition plane (2108) are positioned at an angle (α5) with respect toeach other. In some variations, angle (α5) may be from about 0° to about90° (e.g., from about 20° to about 90°, from about 20° to about 65°).Referring next to FIG. 21B, transition plane (2108) and arch plane(2112) are positioned at an angle (a6) with respect to each other. Incertain variations, angle (α6) may be from about 15° to about 90° (e.g.,from about 30° to about 90° or from about 15° to about 45°). Finally,and referring to FIG. 21C, valve plane (2104) and arch plane (2112) arepositioned at an angle (α7) with respect to each other.

FIGS. 22A-22C illustrate another way in which the curves of a diagnosticcatheter may be defined. As shown there, a diagnostic catheter (2200)comprises a valve curve region (2202) defining a valve plane (2204), atransition curve region (2206) defining a transition plane (2208), andan arch curve region (2210) defining an arch plane (2212). As shown inFIG. 22A, valve curve region (2202) has a radius of curvature (R1) thatmay be, for example, from about 10 millimeters to about 25 millimeters(e.g., from about 10 millimeters to about 20 millimeters, or from about15 millimeters to about 25 millimeters). As shown in FIG. 22B,transition curve region (2206) has a radius of curvature (R2) that maybe, for example, from about 20 millimeters to about 40 millimeters(e.g., from about 20 millimeters to about 35 millimeters, or from about25 millimeters to about 40 millimeters). Finally, and as shown in FIG.22C, arch curve region (2210) has a radius of curvature (R3) that maybe, for example, from about 25 millimeters to about 50 millimeters(e.g., from about 25 millimeters to about 40 millimeters, or from about35 millimeters to about 50 millimeters).

Certain variations of diagnostic catheters having particular shapes havebeen described. However, other variations of diagnostic catheters havingother shapes may be used. The shape of a diagnostic catheter (e.g., thenumber, size, and shape of its curves, etc.) may be at least partiallydetermined, for example, based on the characteristics of the target siteand/or the subject to be treated. FIGS. 23A-23K illustrate differentexamples of curved diagnostic catheters. More specifically, FIG. 23Ashows a diagnostic catheter (2300) including a few wide curves, FIG. 23Bshows a diagnostic catheter (2302) having a couple of curves that are alittle steeper, FIG. 23C shows a diagnostic catheter (2304) having ahelical shape, FIG. 23D shows a diagnostic catheter (2306) that is verysimilar to diagnostic catheter (2300) of FIG. 23A but that has slightdifferences in the positioning of its curves, and FIG. 23E shows adiagnostic catheter (2308) having somewhat of a golf club-type shape,with a relatively straight region (2310), a rounded curve region (2312)distal of relatively straight region (2310), and a small curved tipregion (2314) distal of rounded curve region (2312). FIGS. 23F-23K showdifferent variations of diagnostic catheters (2350), (2360), (2370),(2380), (2390), and (2395), respectively, all having differentcurvatures.

Methods of Making Catheters

Catheters, such as diagnostic catheters, chord manipulation catheters,guide catheters, visualization catheters, and anchor deploymentcatheters, may be made using any suitable method. In some variations, acatheter may be formed using a laying-up or building-up process, inwhich two or more tubular members (e.g., comprising different materials)are combined together to form a catheter. For example, in certainvariations, a catheter may be assembled by providing a liner (e.g., apolytetrafluoroethylene liner), positioning one or more tubular membersover the liner (adjacent to each other and/or over each other), andfusing the various layers together (e.g., by heating the combination).In some variations, one or more braids, coils, etc. may be added intothe layering. Other methods that may be used to form catheters include,but are not limited to, extrusion methods.

In certain variations, a catheter may be placed in a fixture which maybe used to shape the catheter so that it includes one or more curveregions. Such a fixture may be used, for example, to form a diagnosticcatheter, chord manipulation catheter, guide catheter, visualizationcatheter or anchor deployment catheter described here. The fixture maybe used to shape a commercially available catheter, or to shape acustom-made catheter (e.g., assembled using the laying-up processdescribed in the preceding paragraph). In certain variations, thecatheter and fixture may be heated once the catheter has been moldedaround the fixture, to help set the curvature into the catheter. Forexample, the catheter and the fixture may be heated to a temperature ofabout 120° C. to about 140° C. (e.g., about 125° C. to about 135° C.,such as about 130° C.). In some variations, the catheter and the fixturemay be heated for a period of about one hour. The catheter may also becooled for a period of time (e.g., one hour) after heating. It should benoted that in some cases, the dimensions of the catheter may changesomewhat as a result of relaxation during the cooling period. In suchcases, the dimensions of the catheter when it is initially shaped on thefixture may be selected taking this change into account.

In some instances, at least one mandrel or other elongated member may bepositioned within the lumen of the catheter during the shaping process.The mandrel or other elongated member may, for example, help to preventthe lumen of the catheter from losing its patency while the catheter isbeing molded.

FIGS. 24A and 24B depict a variation of a fixture (2400) that may beused to mold a catheter, such as a 9 Fr diagnostic catheter (i.e., adiagnostic catheter having an outer diameter of 3 millimeters). FIG. 24Aprovides a perspective view of the fixture, while FIG. 24B provides anexploded view of the fixture. One or more components of the fixture(e.g., the entire fixture) may be made of, for example, one or morepolymers, such as ULTEM® polyimide thermoplastic resin. Otherappropriate materials may alternatively or additionally be used. FIG.24C illustrates how a catheter may be wound around fixture (2400) sothat the catheter is shaped to have a valve curve region, a transitioncurve region, and an arch curve region, for example. More specifically,FIG. 24C shows a pathway (P) along which a catheter may be positioned onfixture (2400), so that curves may be molded into the catheter. Thedashed lines that form part of pathway (P) are intended to depict thatportion of pathway (P) that is located beneath that region of fixture(2400). During use of fixture (2400), a catheter may be attached to thefixture (e.g., held in place by pins) at a point (2490). Alternativelyor additionally, the catheter may be stabilized with respect to thefixture in one or more other ways. The catheter may then be wound aroundfixture (2400), along pathway (P). Region (2492) of pathway (P)corresponds to the valve curve region of the resulting catheter, region(2494) corresponds to the transition curve region of the resultingcatheter, and region (2496) corresponds to the arch curve region of theresulting catheter. To form these curves, the catheter may be maintainedon the fixture for an appropriate amount of time, and then may beremoved from the fixture once the curves have set into the catheter.

While fixture (2400) depicts one variation of a catheter-shapingfixture, other variations may be used. Alternatively or additionally,other variations of pathways may be used. For example, FIGS. 24D-24Gdepict additional non-limiting variations of fixtures that may be usedto mold or shape a catheter (e.g., according to the method describedabove).

First, FIG. 24D shows a fixture (2450) that may be used to form acatheter (e.g., a 9 Fr catheter, or a catheter having an outer diameterof 3 millimeters) including an arch curve region, a transition curveregion, and a valve curve region. Fixture (2450) comprises an archclamshell portion (2401), dowel pins (2409) and (2410) (e.g., formed ofstainless steel), and an arch portion (2414). Fixture (2450) alsocomprises a round clamshell portion (2407) (e.g., 0.75 inch) and a roundback portion (2406) (e.g., 0.75 inch), as well as a round portion (2405)(e.g., 0.75 inch), a transition cap portion (2404) (e.g., 1 inch), atransition base portion (2402) (e.g., 1 inch), and socket head capscrews (2412) and (2413). Additionally, fixture (2450) comprises a roundportion (2403) (e.g., 1 inch), a socket button head cap screw (2411), atransition cap clamshell portion (2408) (e.g., 1 inch), and an angleblock portion (2415). Fixture (2450) is configured such that when thecatheter is being shaped on the fixture, the catheter has an arch curveregion and a transition curve region defining planes at an angle ofabout 45° relative to each other, and a valve curve region defining aplane that is at an angle of about 135° with respect to the transitioncurve region. However, after the catheter is removed from the fixture,the catheter may relax somewhat, so that these angles may change.

FIG. 24E shows a fixture (2440) that may be used, for example, to form acatheter (e.g., a 9 Fr catheter, or a catheter having an outer diameterof 3 millimeters). While being shaped by the fixture, the catheter mayhave an arch curve region and a transition curve region defining planesat an angle of about 45° relative to each other, and/or a valve curveregion defining a plane that is at an angle of about 1100 with respectto the transition curve region. Of course, while a catheter being shapedin the fixture may have these 45° and 110° angles, after being removedfrom the fixture, the catheter may relax somewhat and these angles maychange. Fixture (2440) comprises an arch portion (2444) and an angleblock portion (2447).

Another variation of a fixture (2430) that may be used, for example, toform a catheter (e.g., a 9 Fr catheter, or a catheter having an outerdiameter of 3 millimeters) is depicted in FIG. 24F. While being shapedby the fixture, the catheter may have an arch curve region and atransition curve region defining planes at an angle of about 35°relative to each other, and/or a valve curve region defining a planethat is at an angle of about 135° with respect to the transition curveregion. As described above, however, while a catheter being shaped inthe fixture may have these 35° and 135° angles, after being removed fromthe fixture, the catheter may relax somewhat and these angles maychange. Fixture (2430) comprises an angle block portion (2435) and anarch portion (2436).

FIG. 24G shows an additional variation of a fixture (2420) that may beused, for example, to form a catheter (e.g., a 9 Fr catheter, or acatheter having an outer diameter of 3 millimeters). While being shapedby the fixture, the catheter may have an arch curve region and atransition curve region defining planes at an angle of about 35°relative to each other, and/or a valve curve region defining a planethat is at an angle of about 110° with respect to the transition curveregion. However, and as described above, while a catheter being shapedin the fixture may have these 35° and 110° angles, after being removedfrom the fixture, the catheter may relax somewhat and these angles maychange. As shown in FIG. 24G, fixture (2420) comprises an arch portion(2426) and an angle block portion (2427).

While the fixtures described above may be used to form a catheter withthree curve regions, in some variations a fixture (including, but notlimited to, one of the above-described fixtures) may be used to form acatheter with only one or two curve regions, or with more than threecurve regions (e.g., by winding the catheter along the fixture in adifferent manner). Alternatively or additionally, a fixture may be usedto form a catheter having one or more other features. Furthermore, incertain variations, multiple fixtures (e.g., 2, 3, 5) may be used toform multiple curves in a catheter.

Chord Manipulation Devices and Methods

In some cases, a catheter may confront one or more obstacles as it isbeing delivered to a target site. The obstacle(s) may make it relativelydifficult or even impossible to access the target site with thecatheter. For example, in a mitral valve repair procedure, it may bedifficult or impossible to access the subannular groove region becauseof the presence of one or more interfering chords in and/or near theregion. In some such cases, the chord or chords may be manipulated tomake the subannular groove region more accessible. Any of a number ofdifferent devices and methods may be used to manipulate chords,non-limiting examples of which will now be discussed in more detail.

Certain variations of chord manipulation devices may be in the form ofchord-cutting devices. The chord-cutting devices may be used, forexample, to cut one or more chords to provide access to a subvalvularspace (e.g., a subannular groove region) in a heart. Chord-cuttingdevices, as well as other chord manipulation devices described here, maybe used with any type of chord, as appropriate. In certain variations,such devices may at least be used to cut one or more tertiary orthird-order chords. As discussed above, it may not be necessary for aheart to have all of its tertiary or third-order chords in order for themitral valve and the overall heart to function sufficiently.

Chord-cutting devices may have any appropriate size, shape, and/orconfiguration, and in some cases, may be tailored for use with aparticular subject's anatomy. FIGS. 58A-58C show one example of avariation of a device and related method for cutting one or more chords.As shown there, a chord-cutting device (5800) comprises an elongatedmember (5801) having a V-shaped blade (5802) in its distal section(5804). In FIGS. 58A-58C, chord-cutting device (5800) is used to sever achord (5806) in the region of a ventricular wall (5808) of a heart.First, and referring to FIG. 58A, chord-cutting device (5800) isadvanced along ventricular wall (5808), toward chord (5806). Ifchord-cutting device (5800) is able to pass between chord (5806) andventricular wall (5808), then chord-cutting device (5800) will not severchord (5806). However, and as shown in FIG. 58B, here chord (5806) istoo close to ventricular wall (5808) to allow for passage ofchord-cutting device (5800) therebetween. Instead, chord (5806) fallsinto a notch (5810) in distal section (5804) of elongated member (5801)(FIG. 58B), and is severed by blade (5802). The result is a severedchord (5806), as shown in FIG. 58C. After the operator has usedchord-cutting device (5800) to sever chord (5806), the operator may, forexample, continue to advance chord-cutting device (5800) along itsoriginal path (e.g., to sever more interfering chords), or may simplywithdraw chord-cutting device (5800) from the body of the subject. Insome cases, after the chord has been severed (and, e.g., after thechord-cutting device has been withdrawn from the body), a catheter maybe routed past the severed chord and to a target site in the heart(e.g., to perform a procedure at the target site).

As noted above, in some cases, the space between a chord and aventricular wall may be sufficiently large to allow for passage ofchord-cutting device (5800), such that chord-cutting device (5800) willnot sever the chord. FIG. 58D depicts an example of such a situation, inwhich a chord-cutting device (5800) passes between a chord (5812) andventricular wall (5808). Because there is sufficient room between chord(5812) and ventricular wall (5808) to allow for clear passage ofchord-cutting device (5800) therethrough, chord-cutting device (5800)passes by chord (5812) without severing it.

Chord-cutting devices such as chord-cutting device (5000) may be made ofany suitable material or materials, and may have any dimensions that areappropriate for delivery of the devices to, and use of the deviceswithin, a heart ventricle.

Of course, while FIGS. 58A-58D show one variation of a chord-cuttingdevice, others suitable variations of chord-cutting devices may be used.For example, FIGS. 59A-59C depict a different variation of achord-cutting device. As shown there, a chord-cutting device (5900)comprises an elongated member (5902) having a groove (5904) in itsdistal portion (5906). A cutting blade (5908) is disposed within groove(5904), and is slidable along a track (not shown) in the groove (e.g.,by actuating a mechanism, such as a slide actuator, in a proximalportion of chord-cutting device (5900)).

FIG. 59A depicts chord-cutting device (5900) as it is advanced along aventricular wall (5910) of a heart, where it confronts a chord (5912).Chord-cutting device (5900) is too large to be able to pass through thespace between chord (5912) and ventricular wall (5910). As a result,during the continued advancement of chord-cutting device (5900), chord(5912) becomes positioned between ventricular wall (5910) andchord-cutting device (5900). As shown in FIGS. 59B and 59C, chord (5912)then slides into groove (5904), and the continued advancement ofchord-cutting device (5900) causes cutting blade (5908) to contact andthereby sever chord (5912). While chord-severing via the continuedadvancement of chord-cutting device (5900) has been described, in somevariations, chord-cutting device (5900) may alternatively oradditionally be used to sever a chord by slidably advancing cuttingblade (5908) along the track in groove (5904), until the cutting bladecontacts and severs the chord. The position of cutting blade (5908) ingroove (5904) may cause cutting blade (5908) to be sheltered, such thatchord-cutting device (5900) is relatively unlikely to cut or damagenon-target tissue. Other blade protection mechanisms or shields mayalternatively or additionally be used. Additionally, in some variations,the dimensions of blade (5908) may be selected so that the blade fitswithin the dimensions of groove (5904).

FIGS. 59A-59C show just one orientation of chord-cutting device (5900)with respect to ventricular wall (5910). However, other chord-cuttingdevice orientations may also be used, as appropriate. For example, FIGS.59D-59F show chord-cutting device (5900) after it has been rotated 180°with respect to ventricular wall (5910) (relative to its orientation inFIGS. 59A-59C). Additionally, as shown there, a chord (5920) isrelatively close to ventricular wall (5910), but still is able to passover the distal-most part of distal portion (5906) as chord-cuttingdevice (5900) is advanced along ventricular wall (5910). As shown, oncegroove (5904) is positioned in the vicinity of chord (5920), chord(5920) slides into groove (5904). In some cases, this may occur becausechord (5920) is relatively close to ventricular wall (5910), such thatchord-cutting device (5900) just fits between the chord and theventricular wall. By contrast, a chord that is relatively spaced apartfrom a ventricular wall may not slide into groove (5904), and insteadmay simply pass over chord-cutting device (5900) as it is advanced.After chord (5920) has slid into groove (5904), the operator maycontinue to advance chord-cutting device (5900) (and/or may slidablyadvance cutting blade (5908) along the track in groove (5904)), untilcutting blade (5908) contacts and severs chord (5920), as shown in FIG.59F.

Other variations of chord-cutting devices may be used. For example,FIGS. 60A-60J depict additional variations of a device and method forcutting one or more chords. Referring first to FIG. 60A, a chord-cuttingdevice (6000) comprises a housing (6002) having a grooved portion(6004). As shown in FIG. 60B, which provides a cross-sectional view ofchord-cutting device (6000), the device also comprises a cutting member(6006) slidably disposed within housing (6002), where the cutting member(6006) comprises a curved elongated body (6008) and a cutting blade(6010) coupled to the body. Referring again to FIG. 60A, housing (6002)comprises a more proximal portion (6009) having a dimension (D1) and amore distal portion (6011) having a corresponding dimension (D2) that issmaller than dimension (D1). While not shown, housing (6002) includes aslot within the region of grooved portion (6004), such that cuttingmember (6006) can pass through grooved portion (6004), as shown in FIG.60C. When cutting member (6006) passes through grooved portion (6004), aportion of cutting member (6006) extends outside of housing (6002), suchthat it can contact chords positioned within grooved portion (6004). Itshould be noted, of course, that this is just one possible configurationof a cutting member, and other configurations may be employed. As anexample, in some variations, an entire cutting member may extend outsideof a chord-cutting device housing during at least a portion of achord-cutting process. As another example, in certain variations, achord-cutting device may comprise a housing having multiple groovedportions.

Referring now to FIG. 60D, during use an operator may positionchord-cutting device (6000) between a ventricular wall (6012) and achord (6014). The operator may then advance chord-cutting device (6000)in the direction of arrow (A1), such that chord (6014) becomespositioned within grooved portion (6004) (FIG. 60E). As the operatorcontinues to advance chord-cutting device (6000) in the direction ofarrow (A1), chord (6014) begins to travel up the other side of groovedportion (6004). However, in this case, while chord (6014) was able topass over distal portion (6011) of chord-cutting device (6000), chord(6014) is not able to pass over the larger proximal portion (6009). As aresult, chord-cutting device (6000) is no longer capable of beingadvanced in the direction of arrow (A1). When this occurs, the operatormay experience the resistance to further advancement as a tactileindication of the presence of an obstacle in the path of chord-cuttingdevice (6000). Such a tactile indication may also be provided by othervariations of chord-cutting devices. Alternatively or additionally, achord-cutting device may comprise one or more sensors and/or otherindicators that may notify the operator of the presence of anobstructing chord. Moreover, in some variations, the location of a chordin the path of a device may be determined using one or morevisualization methods, such as echocardiography (e.g., 3Dechocardiography), magnetic resonance imaging (MRI), and/or computedtomography (CT). In some variations, the location of a chordmanipulation device with respect to a heart wall may be verified using,for example, contrast agent and X-ray fluoroscopy.

Upon becoming aware of the presence of an obstacle in the path ofchord-cutting device (6000), the operator may proximally withdrawchord-cutting device (6000), so that chord (6014) becomes positionedwithin grooved portion (6004), as shown in FIG. 60G. Then, and as shownin FIG. 60H, the operator may actuate cutting member (6006) to translateit across grooved portion (6004), where cutting blade (6010) contactsand cuts chord (6014) (FIG. 60I). The result is a severed chord (6014),as shown in FIG. 60J. Of course, as with all chord manipulation devicesand methods described here, the operator may simply elect to withdrawthe entire device when it comes into contact with a chord, rather thanmanipulating (e.g., cutting) the chord, if it is appropriate to do so.

Because cutting member (6006) is disposed within housing (6002) when notin use, inadvertent tissue cutting or damage may be avoided. Moreover,in some cases, chord-cutting device (6000) may include one or moresafety mechanisms to prevent inadvertent advancement of cutting member(6006). For example, a button or switch may be activated to deploy abarrier in the slot (not shown) in groove portion (6004), and to therebyprevent advancement of cutting member (6006) within the slot.Additionally, the design of cutting device (6000) may help to controlthe cutting of a chord. For example, the design may allow for chords tobe positioned within grooved portion (6004) in a particular way, suchthat the chords are stabilized prior to cutting.

Of course, cutting member (6006) is only one variation of a cuttingmember, and other suitable variations may be used. For example, cuttingmembers having different sizes and/or shapes may be used, and in somevariations, multiple cutting members may be used. As an example, FIG.60K shows another variation of a cutting member (6050). As shown there,cutting member (6050) comprises a curved elongated body (6052) and acutting blade (6054) coupled to the curved elongated body, where cuttingblade (6054) is sloped in a direction opposite that of cutting blade(6010) described above. As another example, FIG. 60L shows a cuttingmember (6060) comprising a curved elongated body (6062) and a curvedcutting blade (6064). Curved cutting blade (6064) may, for example,provide highly controlled chord cutting. For example, the blade'sposition at the very end of cutting member (6060), and within thecontour of its curve, may make it highly unlikely that the blade willprematurely cut a chord. As an additional example, FIG. 60M shows acutting member (6070) comprising a curved elongated body (6072) and acutting blade (6074) that is both curved and notched. While FIGS.60K-60M show specific exemplary variations of cutting members, otherappropriate cutting members may alternatively or additionally be used ina chord-cutting device. For example, in some variations, a chord-cuttingdevice may comprise a cutting member that does not comprise a curvedelongated member, and/or that just comprises one or more blades. As anexample, FIGS. 60N and 60O illustrate a method that comprises severing achord (6080) with a chord-cutting device (6084). As shown there,chord-cutting device (6084) comprises a cutting member (6082) slidablydisposed within a track (not shown) of chord-cutting device (6084).Cutting member (6082) is in the form of a cutting blade (6086).

Additional variations of chord-cutting devices are contemplated. As anexample, FIG. 61 shows a chord-cutting device (6100) comprising a body(6102) having a V-shaped opening (6104) formed therein, and a cuttingblade (6106) disposed within the opening. During use, an operator mayadvance chord-cutting device (6100) adjacent a ventricular wall (6108),and use it to sever chords that prevent chord-cutting device (6100) frompassing between them and the ventricular wall. The obstructing chordsmay be swept into V-shaped opening (6104), where they may be severed bycoming into contact with cutting blade (6106).

In some variations, a chord-cutting device may comprise one or moreexpandable members. In some such variations, the expandable members maycomprise inflatable members, such as balloons. The expandable membersmay be used, for example, to assess whether it is necessary to sever oneor more chords to provide a target site with enhanced accessibility.

As an example, FIG. 62A show a chord-cutting device (6200) comprising anelongated member (6202) having a notch (6204) formed therein, and aninflatable member (6206) disposed at the distal end of the elongatedmember. In FIG. 62A, inflatable member (6206) is inflated. During use,chord-cutting device (6200) may be advanced through a subvalvular spaceof a heart with inflatable member (6206) in its inflated state. Theinflatable member may be fully inflated, or may be inflated to less thanits full inflation capacity. FIG. 62A shows chord-cutting device (6200)when inflatable member (6206) is unable to pass between a chord (6210)and a ventricular wall of the heart. When this occurs, the operatorgenerally will not be able to advance chord-cutting device (6200) anyfurther, and may experience a tactile sensation indicating that thechord-cutting device is stuck. In response, and referring now to FIG.62B, the operator may at least partially deflate inflatable member(6206), so that chord-cutting device (6200) is able to pass betweenchord (6210) and ventricular wall (6208). As shown in FIG. 62C, theoperator may then actuate a cutting blade (6212) of chord-cutting device(6200), such that the cutting blade appears through notch (6204).Chord-cutting device (6200) may then be advanced toward chord (6210) sothat cutting blade (6212) contacts and cuts the chord (as shown in FIG.62D), thereby resulting in a severed chord (6210) (FIG. 62E). In somecases, after the chord has been severed, cutting blade (6212) may beretracted back into notch (6204) and/or chord-cutting device (6200) maybe further advanced through the subvalvular space of the heart (e.g., tosever any additional chords that may present obstacles to catheteradvancement).

FIGS. 63A-63E depict another variation of a chord-cutting device (6300).As shown there, chord-cutting device (6300) comprises an outer tubularmember (6302) and an inner elongated member (6304) disposed within alumen of outer tubular member (6302). During use, an operator mayposition chord-cutting device (6300) so that outer tubular member (6302)is adjacent a heart tissue wall (6306), and may advance chord-cuttingdevice (6300) along the heart tissue wall. During this advancement,chord-cutting device (6300) may approach one or more chords, such aschord (6308) in FIG. 63A. As shown in FIG. 63A, the space (S) betweenchord (6308) and heart tissue wall (6306) is not large enough forchord-cutting device (6300) to pass therethrough. In response, andreferring now to FIG. 63B, the operator may proximally withdraw outertubular member (6302), and may attempt to push inner elongated member(6304) between chord (6308) and heart tissue wall (6306). As shown inFIG. 63C, here there is sufficient space for inner elongated member(6304) to pass between the chord and the heart tissue wall. Referringnow to FIG. 63D, the operator may actuate a blade (6310) or othercutting member from chord-cutting device (6300) and, as shown in FIG.63E, may continue to advance chord-cutting device (6300) until blade(6310) severs chord (6308). In cases in which there is insufficientspace for inner elongated member (6304) to pass between a chord and aheart tissue wall, the operator may, for example, advance a smallerchord-cutting device to the obstructed location and use that smallerchord-cutting device to cut the chord.

Still other variations of chord-cutting devices may be used. As anexample, FIG. 64A depicts another variation of a chord-cutting device(6400) comprising an outer tubular member (6402) having a lumen (6404),and an inner rotatable member (6406) disposed within lumen (6404). Innerrotatable member (6406) comprises an elongated body portion (6408) and arounded asymmetrical head portion (6410). The rounded shape of headportion (6410) may, for example, cause chord-cutting device (6400) to berelatively atraumatic and unlikely to harm body tissue during use. Headportion (6410) comprises a shelf (6412) configured to align with asharpened edge (6413) of outer tubular member (6402). During use, anoperator may elect to cover sharpened edge (6413) with shelf (6412), orto expose sharpened edge (6413). For example, sharpened edge (6413) maybe covered by shelf (6412) during initial advancement of chord-cuttingdevice (6400) within the body, and then uncovered when sharpened edge(6413) is needed to sever a chord.

As an example, FIG. 64A shows chord-cutting device (6400) being advancedalong a heart tissue wall (6414) and toward a chord (6416). During thisadvancement, shelf (6412) covers sharpened edge (6413). As shown in FIG.64A, chord-cutting device (6400) is too large to fit between hearttissue wall (6414) and chord (6416). Upon determining that this is thecase, the operator may partially proximally withdraw chord-cuttingdevice (6400), as shown in FIG. 64B. Referring now to FIG. 64C, theoperator may then rotate inner rotatable member (6406), so that shelf(6412) no longer covers sharpened edge (6413). Then, and as shown inFIG. 64D, chord-cutting device (6400) may once again be advanced towardchord (6416), so that sharpened edge (6413) contacts and thereby severschord (6416). While one variation of an inner member is shown, it shouldbe understood that other variations (e.g., having different shapes) maybe used, as appropriate. As an example, in some variations, an innermember may itself be tubular. This may, for example, allow an operatorto deliver one or more therapeutic agents through the inner member andinto the body during use.

FIGS. 65A-65E illustrate additional variations of a chord-cutting deviceand related method for cutting one or more chords. As shown there, achord-cutting device (6500) comprises an elongated member (6502) and acurved cutting member (6504) projecting from an outer surface of theelongated member. Curved cutting member (6504) comprises an outerrounded surface (6506) and an inner surface (6508) including a cuttingblade (6510). Referring now specifically to FIG. 65A, during usechord-cutting device (6500) may be advanced along a heart tissue wall(6512) and toward a chord (6514). As shown in FIG. 65A, chord-cuttingdevice (6500) may become stuck between chord (6514) and heart tissuewall (6512) when cutting member (6504) is in its fully projected state.However, the operator may continue to push chord-cutting device (6500),until the portion of chord-cutting device (6500) comprising curvedcutting member (6504) squeezes between chord (6514) and heart tissuewall (6512), as shown in FIG. 65B. In some cases, cutting member (6504)may have some flexibility or springiness that allows it to be pusheddownward (i.e., closer to elongated body portion (6502)), and to fitbetween chords and heart tissue wall (6512) in this way. Referring nowto FIG. 65C, eventually the portion of cutting device (6500) comprisingcurved cutting member (6504) passes by chord (6514). Since cuttingmember (6504) is no longer restrained by chord (6514), it may assume itsoriginal position. Next, and as shown in FIG. 65D, the operator mayproximally withdraw chord-cutting device (6500) until cutting member(6504) contacts chord (6514) and cutting blade (6510) severs chord(6514). FIG. 65E shows chord (6514) after it has been severed. While notshown here, in some variations, chord-cutting device (6500) may bedelivered to a target site in a delivery device (e.g., a tubular membersuch as a catheter) that temporarily covers curved cutting member (6504)(e.g., preventing inadvertent tissue-snagging or other tissue damage bythe cutting member during delivery).

In some variations, a chord-cutting device may comprise one or moreradiopaque markers and/or markings. These markers and/or markings may beused, for example, to help align the device properly within the heartduring use. For example, FIG. 66A shows a chord-cutting device (6600)comprising an elongated member (6602), an inflatable member (6604), anda cutting blade (6606). Chord-cutting device (6600) further comprises aradiopaque projection (6608). Radiopaque projection (6608) may be used,for example, to help determine the orientation of chord-cutting device(6600) under X-ray fluoroscopy during use, and/or to let the operatorknow the approximate positioning of cutting blade (6606) during use.While one variation of a radiopaque projection has been depicted, itshould be understood that other variations of radiopaque projections mayalternatively or additionally be employed. Moreover, while a radiopaqueprojection has been shown, some variations of chord-cutting devices mayalternatively or additionally comprise other forms of radiopaque markersor markings. Additionally, in some cases multiple radiopaque markersand/or markings may be used.

FIG. 66B shows a chord-cutting device (6620) comprising an elongatedmember (6622), an inflatable member (6624), and a cutting blade (6626).Chord-cutting device (6620) also includes a number of radiopaquemarkings (6628), each in the form of an “A,” along elongated member(6622). As another example, FIG. 66C shows a cutting device (6640)comprising an elongated member (6642), an inflatable member (6644), anda cutting blade (6646), where elongated member (6642) includes threeradiopaque markings (6648), each in the form of a “G.” Of course, whilecertain letters have been shown, other letters, numbers, designs, andthe like may be used, and any suitable combination of markings (e.g.,combinations of letters and numbers) may be used. Radiopaque markers ormarkings may be employed with any of the devices described herein asappropriate, and are not limited to use with chord-cutting devices.

While chord-cutting devices and methods have been described, in somevariations, chords may alternatively or additionally be manipulated inone or more other ways. For example, FIGS. 67A-67D show a device andmethod for manipulating one or more chords by gathering the chords(e.g., to move them out of the way of a catheter being tracked along asubannular groove region). Referring now to FIG. 67A, a chord-gatheringdevice (6700) comprising an elongated member (6702) may be advanced intoa left ventricle (LV) of a heart (H). As shown in FIGS. 67B and 67C, ahook (6704) may be advanced from elongated member (6702) and may behooked around chordae tendineae (CT) in left ventricle (LV) (FIG. 67C).In some variations, the chords may be visualized (e.g., using one ormore of the visualization methods described above) prior to, during,and/or after such hooking. Once the chords have been hooked, andreferring now to FIG. 67D, hook (6704) may be drawn up toward mitralvalve leaflets (MVL), thereby gathering the chords (and, e.g., providingadditional space for advancement of a catheter within left ventricle(LV)). Of course, while a hook has been described, other variations ofchord manipulation devices may alternatively or additionally compriseone or more different mechanisms for manipulating chords. Additionally,in certain variations, a device may be able to serve more than one chordmanipulation function. For example, a device may be capable of bothcutting and gathering chords to move and/or re-position the chords.

Anchor Deployment Methods

As described above, in certain variations, after a diagnostic catheterhas been used to assess the accessibility of a mitral valve region, aprocedure may be performed to deploy coupled anchors (e.g., tetheredanchors) to the region. FIGS. 25A-25D illustrate a variation of ananchor deployment method.

As shown in FIG. 25A, in one variation, a distal portion (2502) of aguide catheter (2500) may be positioned in a desired location under avalve leaflet (L) and adjacent a ventricular wall (VW) in a heartventricle having a chorda tendinea (CT). The valve annulus (VA)generally comprises an area of heart wall tissue at the junction of theventricular wall (VW) and the atrial wall (AW) that is relativelyfibrous and, thus, significantly stronger than leaflet tissue and otherheart wall tissue. It is noted, however, that considerable structuralvariations of the annulus exist within patient populations, and that anattempted delivery of an implant to the valve annulus (VA) may insteadresult in the implant contacting or attaching to the tissue adjacent tothe valve annulus. The term “annular tissue” as used herein shallinclude the valve annulus and the tissue adjacent to or surrounding thevalve annulus.

Distal portion (2502) of guide catheter (2500) may be advanced intoposition generally under valve annulus (VA) by any suitable technique,some of which are described below. Distal portion (2502) of guidecatheter (2500) may be used to deliver one or more anchors to the valveannular tissue, to stabilize and/or expose the annulus, or both. In onevariation, using guide catheter (2500) having a flexible elongate body,flexible distal portion (2502) may be positioned in the heart ventricleat the level of valve leaflet (L) using any of a variety of accessroutes described herein. Distal portion (2502) may be advanced under theposterior valve leaflet into a space such as subannular groove region(2504) or in subvalvular space (2506). It has been found that when guidecatheter (2500) is passed, for example, under the mitral valve via anintravascular approach, guide catheter (2500) may be inserted intosubannular groove region (2504) or subvalvular space (2506) and advancedeither partially or completely around the circumference of the valve.Once in subannular groove region (2504) or subvalvular space (2506),distal portion (2502) of guide catheter (2500) may be positionedproximate to the intersection of the valve leaflet(s) and ventricularwall (VW), which is near valve annulus (VA). These are but examples ofpossible access routes of a guide catheter to a valve annulus, and anyother appropriate access routes may be used.

In some variations, it may be advantageous to provide guide catheter(2500) with a curvable portion having a radius in an expanded/curvedstate that is greater than a radius of the valve annulus, the subannulargroove region or the ventricular chamber. The relative size of thisportion of guide catheter (2500), when positioned within the smallersized ventricle, may exert a radially outward force that may improve thesurface contact between guide catheter (2500) and left ventricle (LV).For example, in one variation, guide catheter (2500) in the expandedstate may have a radius that is about 25% to about 50% larger than thevalve annulus. Additionally, certain variations of guide catheters mayfurther include one or more expandable members (e.g., balloons) that mayexpand to urge or press or wedge the guide catheter into a target site(e.g., in the subvalvular space).

In some variations, guide catheter (2500) (and specifically distalportion (2502)) may be used to stabilize and/or expose the valve annulusor annular tissue. Other catheters may alternatively or additionally beused to stabilize and/or expose the valve annulus or annular tissue.Such stabilization and exposure are described, for example, in U.S.patent application Ser. No. 10/656,797 (published as US 2005/0055087A1), which is incorporated herein by reference in its entirety. Forexample, distal portion (2502) may be positioned generally under theannular tissue, and force may be applied to distal portion (2502) tostabilize valve annulus (VA) or the annular tissue, as shown in FIG.25B. Such force may be directed in any suitable direction to expose,position and/or stabilize the annulus or annular tissue. In anotherexample, an upward and lateral force is shown in FIG. 25B by thesolid-headed arrow drawn from the center of distal portion (2502). Inother examples, only upward, only lateral, or any other suitableforce(s) may be applied. With application of force to distal portion(2502), the annular tissue may rise or project outwardly, thus exposingthe annulus for easier viewing or access. The applied force may alsostabilize valve annulus (VA) or the valve annular tissue, therebyfacilitating surgical procedures and visualization.

In some variations, an anchor deployment catheter may exert additionalforce after the first anchor is engaged to body tissue. The first anchormay provide additional leverage and stability for manipulating theanchor deployment catheter. Referring to FIGS. 25C and 25D, an anchordeployment catheter (2508) is schematically shown deploying an anchor(2510) to a valve annulus (VA) or annular tissue. Variations of anchordeployment catheters are described, for example, in U.S. patentapplication Ser. No. 12/366,553 (published as US 2009/0222083 A1), U.S.Provisional Application Ser. No. 61/160,230, filed on Mar. 13, 2009, andU.S. Provisional Application Ser. No. 61/178,910, filed on May 15, 2009,all of which are incorporated herein by reference in their entirety.Anchor (2510) is shown first housed within anchor deployment catheter(2508) in FIG. 25C, and then deployed to valve annulus (VA) or toannular tissue, as depicted in FIG. 25D. Of course, although thedeployment and position of anchor (2510) is described with respect tovalve annulus (VA), one or more anchors (2510) may miss valve annulus(VA) and attach to other structures or tissues accessible fromsubannular groove region (2504) or generally from subvalvular space(2506).

As shown, in some variations, anchors (2510) may have a relativelystraight configuration when housed in anchor deployment catheter (2508),with two penetrating tips and a loop in between the tips. Upondeployment from anchor deployment catheter (2508), the tips of an anchor(2510) may curve in opposite directions to form two semi-circles,circles, ovals, overlapping helices or the like. This is but one exampleof a type of self-securing anchor which may be deployed to annulartissue. Additional anchor variations are described, for example, in U.S.patent application Ser. No. 11/202,474 (published as US 2005/0273138A1), which is incorporated herein by reference in its entirety. Incertain variations, multiple coupled anchors (2510) may be deployed, andthe anchors (2510) may be drawn together to reduce the annulardimensions.

In some variations, one or more self-forming anchors (2600) may bestored in an anchor deployment device in a straightened configuration,coupled with a tether (2602), as shown in FIG. 26A. Anchors (2600) maybe held or restrained in that straightened state, while their deployedconfiguration is non-linear or curved. Arms (2601) meet at a junctionsection (2603), which is slidably coupled to tether (2602). In certainvariations, junction section (2603) may comprise an open or closed loopconfiguration and may change in size or configuration when arms (2601)are deployed. In this particular variation, as arms (2601) of anchor(2600) are released from the delivery system, arms (2601) are permittedto resume their deployed configuration, penetrating the tissue (T) alonga penetration pathway. As the distal portions of arms (2601) regaintheir deployed configurations, arms (2601) will generally separate andreorient toward the tissue surface (depicted as open-headed arrows). Insome variations, the penetration pathways may be curved, so that asanchor (2600) further penetrates into tissue (T), junctional section(2603) of anchor (2600) will continue along a similar pathway as thearms (2601). This may reduce the degree of tissue compression orstretching as anchor (2600) is deployed, which in turn may also reducethe resulting arrythmogenic risk, if any, from anchor deployment. Thehorizontal and vertical forces generated (depicted as open-headedarrows) by arms (2601) may also result in a counterforce which causesjunction section (2603) to be brought toward the tissue surface(downward-pointing open arrows) and may even pull portions of junctionsection (2603) into tissue (T), as shown in FIG. 26B. Once anchor (2600)is fully deployed (FIG. 26C), anchor (2600) may be substantiallyembedded in tissue (T).

Portions of tether (2602) coupled to junction section (2603) are alsobrought closer to the surface of tissue (T). Bringing tether (2602)closer to tissue (T) may be beneficial because a greater proportion ofthe cross-sectional blood flow path, as bordered by tether (2602), ispreserved. As a result, the risk that any subsequent catheters orimplanted components inserted into the heart chamber or valve will snagor damage tether (2602) may be reduced. Additionally, the degree ofhemolysis, as compared to a tether that crosses the mitral flow pathwayfarther from the tissue surface, may be reduced as well.

FIGS. 26D-26F depict different variations of anchor deployments intoannular tissue. For example, FIG. 26D shows one variation where oneanchor (2604) has been deployed into an annulus (A), while anotheranchor (2605) has been deployed slightly below annulus (A), in thesubannular groove. The implant shown in FIG. 26E comprises a series ofanchors (2606) that have been deployed into the subannular groove,slightly below annulus (A). In this variation, the anchors (2606) arecoupled by a tether (2608). In the variation depicted in FIG. 26F, eachanchor (2610) has been deployed into annulus (A). Here the anchors areshown as T-tags, although other types of anchors may alternatively oradditionally be used, as appropriate. It should be understood that whenreference is made to “annular tissue,” it is meant to encompass theannulus itself, as well as tissue in close proximity to the annulus,such that implant (or anchor) deployment into the annular tissue canaccomplish a change in the annulus anatomy (e.g., a reduction in annuluscircumference). Consequently, deployment of anchors into “annulartissue” includes at least each of the variations depicted in FIGS.26D-26F.

Various anchor designs and deployment methods are disclosed, forexample, in U.S. patent application Ser. No. 10/741,130 (published as US2004/0193191 A1); Ser. No. 10/792,681 (published as US 2004/0243227 A1);Ser. No. 10/900,980 (published as US 2005/0107811 A1); Ser. No.11/255,400 (published as US 2006/0129188 A1); and Ser. No. 10/901,555(published as US 2006/0058817 A1), all of which are incorporated hereinby reference in their entirety. Various anchor designs and deploymentmethods are also disclosed, for example, in U.S. patent application Ser.No. 11/202,474 (published as US 2005/0273138 A1), which was previouslyincorporated by reference in its entirety. It should also be noted thatin addition to one or more anchors, an implant may comprise a fabric ormesh, or an annuloplasty device or prosthesis, such as a ring, partialring, or band, alone or in combination with one or more anchors. Forexample, the implant may be any of those implants described in U.S.patent application Ser. No. 10/461,043 (issued as U.S. Pat. No.6,986,775); Ser. No. 10/656,797 (published as US 2005/0055087 A1); Ser.No. 10/741,130 (published as US 2004/0193191 A1); Ser. No. 10/776,682(published as US 2005/0107810 A1); Ser. No. 10/792,681 (published as US2004/0243227 A1); Ser. No. 10/901,019 (published as US 2005/0065550 A1);Ser. No. 10/901,444 (published as US 2006/0025784 A1); Ser. No.10/901,455 (published as US 2006/0025750 A1); Ser. No. 10/901,554(published as US 2005/0107812 A1); and Ser. No. 10/901,555 (published asUS 2006/0058817 A1), all of which are incorporated herein by referencein their entirety.

Another variation of a method for applying a plurality of tetheredanchors (2726) to the annular tissue of a heart is shown in FIGS.27A-27F. As shown in FIG. 27A, an anchor deployment catheter (2720) isfirst contacted with valve annulus (VA) or annular tissue such thatopenings (2728) are oriented to deploy anchors (2726) into the tissue.Such orientation may be achieved by any suitable technique. In onevariation, for example, a housing (2722) having an ellipticalcross-sectional shape may be used to orient openings (2728).Alternatively or additionally, various radiopaque markings may beincluded on anchor deployment catheter (2720), so that anchor deploymentcatheter (2720) may be oriented using X-ray fluoroscopy. Contact betweenhousing (2722) and the annular tissue may be enhanced by expanding anexpandable member (2724) to wedge housing (2722) within the deepestportion of the subannular groove region.

Generally, anchor deployment catheter (2720) may be advanced into anysuitable location for treating any valve or body tissue by any suitableadvancement or device placement method. For example, in one variation aguide member may first be advanced in a retrograde fashion through anaorta, typically via access from a femoral artery. It should be noted,however, that access may be obtained through other suitable vessels aswell (e.g., the jugular artery). Similarly, other suitable methods ofaccessing the subannular groove may also be used, including minimallyinvasive thoracotomy techniques (e.g., mini-thoracotomy) and/orminimally invasive sternotomy techniques (e.g., mini-sternotomy).

The guide member may be passed into the left ventricle of the heart andthus into the space formed by the mitral valve leaflets, the leftventricular wall and chordae tendineae of the left ventricle. Once inthis space, the guide member may be advanced along a portion (or all) ofthe circumference of the mitral valve. A sheath (2740) may be advancedover the guide member within the space below the valve leaflets, and theguide member may be removed through sheath (2740). In some variations,the guide member may comprise a steerable guide catheter. Anchordeployment catheter (2720) may then be advanced through the sheath to adesired position within the space, and sheath (2740) may be removed. Inother variations, a guide tunnel (not shown) may be passed through thesheath to provide additional stability and to facilitate positioning ofanchor deployment catheter (2720).

As shown in FIG. 27B, when anchor deployment catheter (2720) ispositioned in a desired location for deploying anchors (2726), an anchorcontacting member (2730) disposed within the anchor deployment membermay be retracted (e.g., using pull cord (2732), FIG. 27A) to contact andapply force to a most-distal anchor (2726). This force may cause anchor(2726) to deploy through an opening (2728) and into valve annulus (VA)or annular tissue. FIG. 27C shows anchor (2726) further deployed out ofopening (2728) and into valve annulus (VA) or annular tissue. FIG. 27Dshows valve annulus (VA) transparently, so that further deployment ofanchors (2726) can be seen. As shown, in one variation, anchors (2726)include two tips that move in opposite directions upon release fromhousing (2722) and upon contacting valve annulus (VA) or annular tissue.Between the two tips, an anchor (2726) may be looped or may have anyother suitable eyelet or other device for allowing slidable couplingwith a tether (2734).

Referring now to FIG. 27E, anchors (2726) are seen in their fullydeployed or nearly fully deployed shape, with each tip (or “arm”) ofeach anchor (2726) having curved to form a circle or semi-circle. Insome variations anchors (2726) may have any other suitable deployed andundeployed shapes, as described more fully above. FIG. 27F shows anchors(2726) deployed into valve annulus (VA) or annular tissue and coupled totether (2734), with the distal-most anchor (2726) coupled to tether(2734) at an attachment point (2736). At this stage, tether (2734) maybe tensioned to reduce the annular dimensions, and may thereby reducevalve regurgitation. In some variations, valve function may be monitoredby means such as echocardiogram and/or fluoroscopy, and tether (2734)may be tensioned, loosened, and adjusted to achieve a desired amount ofannular reduction as evident via the employed visualizationtechnique(s). When a desired amount of annular reduction is achieved,the implant may be fixed using any of a variety of termination devicesand methods.

For example, in one variation, tensioning tether (2734), attachingtether (2734) to most-proximal anchor (2726), and cutting tether (2734)may be achieved using a termination device (not shown). The terminationdevice may comprise, for example, a catheter advanceable over tether(2734), where the catheter includes a cutting member and a knot (e.g.,formed of a nickel-titanium alloy such as Nitinol) or other attachmentmember for attaching tether (2734) to the most proximal anchor. In somevariations, the termination catheter may be advanced over tether (2734)to a location at or near the proximal end of the tethered anchors(2726). It may then be used to apply opposing force to the most proximalanchor (2726) while tether (2734) is tensioned. Attachment and cuttingmembers may then be used to attach tether (2734) to the most proximalanchor (2726), and to cut tether (2734) just proximal to the mostproximal anchor (2726). Such a termination device is only one possibleway of accomplishing the cinching, attachment and cutting steps, and anyother suitable devices and/or techniques may be used. Additional devicesand methods for terminating (e.g., cinching and fastening) aredescribed, for example, in U.S. patent application Ser. No. 11/232,190(published as US 2006/0190030 A1) and Ser. No. 11/270,034 (published asUS 2006/0122633 A1), both of which are incorporated herein by referencein their entirety. Additional devices and methods for terminating (e.g.,cinching and fastening) are also described, for example, in U.S. patentapplication Ser. No. 12/480,568, filed on Jun. 8, 2009, which isincorporated herein by reference in its entirety. In some variations,the termination device may be located in the same heart chamber as theremaining portions of the implant, which may permit the implant to bewholly implanted in a single heart chamber. In other variations,however, a portion of the implant may pass transmurally through a septalwall or an outer wall of a heart chamber. In these variations, thetermination member and optionally one or more anchors may be located ina different heart chamber.

In some variations, it may be advantageous to deploy a first number ofanchors (2726) along a first portion of annular tissue, cinch the firstanchors to achieve a desired reduction in annular dimensions in thatportion of the annular tissue, move the anchor deployment catheter(2720) to another portion of the annular tissue, and deploy and cinch asecond number of anchors (2726) along a second portion of the annulartissue. Such a method may be more convenient, in some cases, thanextending anchor deployment catheter (2720) around all or most of thecircumference of the annular tissue, and may allow a shorter, moremaneuverable housing (2722) to be used.

Although a preferred access route to the subannular groove region orsubvalvular space is a retrograde route through the aorta to the heart,other access routes may also be used. Access to the heart may also betransthoracic, with a delivery device being introduced into the heartvia an incision or port in the heart wall. Even open heart surgicalprocedures may benefit from the methods and devices described herein. Insome variations, hybrid access involving a combination of access methodsdescribed herein may be used. In one specific example, dual access to avalve may be achieved with a combination of venous and arterial accesssites. User manipulation of both ends of a guidewire placed across avalve may improve positioning and control of the catheter and theimplants. In other examples of hybrid access, both minimally invasiveand surgical access may be used to implant one or more cardiac devices.

Other variations of methods may also include treatment of the tricuspidvalve annulus, tissue adjacent the tricuspid valve leaflets, or anyother cardiac or vascular valve. Thus, although the description hereindiscloses specific examples of devices and methods for mitral valverepair, the devices and methods may be used in any suitable procedure,both cardiac and non-cardiac. For example, in certain variations, themitral valve reshaping devices and procedures may be used with thetricuspid valves also, and some variations may also be adapted for usewith the pulmonary and aortic valves. Likewise, the other examplesprovided below are directed to the left ventricle, but the devices andmethods may also be adapted by one of ordinary skill in the art for usein the right ventricle or either atrium. Additionally, in somevariations the devices and methods may be used with the great vessels ofthe cardiovascular system, for example, to treat aortic root dilatation.

Access to the other chambers of the heart may be performed throughpercutaneous or venous cut-down access, including but not limited totransjugular, subclavicular and femoral vein access routes. When venousaccess is established, access to the right atrium, the right ventricle,the tricuspid valve and other right-sided cardiac structures can occur.Furthermore, access to left-sided heart structures, such as the leftatrium, left ventricle, mitral valve and aortic valve, may besubsequently achieved by performing a transseptal puncture procedure.Referring to FIG. 28 with a heart (H) shown in cross-section, atransseptal puncture is traditionally performed using a Mullinsintroducer sheath with a Brockenbrough curved needle through theinteratrial septum to access the left atrium (LA), but any of a varietyof other transseptal puncture devices or kits may also be used. Afterpuncturing through left atrium (LA), supravalvular access to the mitralvalve may be achieved by a guide catheter (2850) having a tubular body(2854), with the distal portion (2852) of the guide catheter enteringthe subvalvular space (2806). Antegrade access to the left ventricle(LV) may also occur by crossing the mitral valve. Similarly, access fromthe right ventricle (RV) to left ventricle (LV) may be obtained bytransseptal puncture of the ventricular septum. In still othervariations, a catheter device may access the coronary sinus and a valveprocedure may be performed directly from the sinus.

Surgical approaches that may be used include, but are not limited to,transcatheter procedures made through surgical incisions in the aorta ormyocardium. In one particular variation, depicted in FIG. 29, atransapical approach with a surgical delivery device (2914) is utilized,to provide a guide catheter (2902) with a more linear route to thesubvalvular space. The transapical approach also reduces potentialeffects of a myocardial incision on cardiac output, as the apical wall(2912) typically contributes less mechanical effect on left ventricularejection fraction compared to other sections of the myocardial wall.

Kits are also described here. In some variations, the kits may includeat least one diagnostic catheter, at least one chord manipulationdevice, at least one guide catheter, and/or at least one visualizationcatheter. In certain variations, the kit may further include at leastone pigtail catheter, at least one guidewire, at least one sheath, atleast one guide tunnel, and/or at least one anchor deployment catheter.In some variations, a kit may include multiple (e.g., 2, 3, 4, 5)different diagnostic catheters, such as diagnostic catheters havingdifferent shapes and/or sizes. Alternatively or additionally, a kit mayinclude multiple (e.g., 2, 3, 4, 5) different guide catheters, such asguide catheters having different shapes and/or sizes, and/or may includemultiple different visualization devices, such as visualizationcatheters having different shapes and/or sizes, and/or may includemultiple different anchor deployment catheters, such as anchordeployment catheters having different sizes and/or shapes. In somevariations, a kit may include multiple different chord manipulationdevices, such as different types of chord manipulation devices and/orchord manipulation devices having different sizes. In certainvariations, a kit may include one or more cinching devices and/or one ormore termination devices (e.g., locking devices, cutting devices, orcombination locking and cutting devices). Of course, instructions foruse may also be provided with the kits.

EXAMPLES

The following examples are intended to be illustrative and not to belimiting.

Example 1

FIG. 30A shows a computer illustration of a diagnostic catheter (3000).As shown there, diagnostic catheter (3000) comprises a valve curveregion (3002), a transition curve region (3004), and an arch curveregion (3006).

Referring now to FIG. 30B, diagnostic catheter (3000) also comprises aregion (3008) that is proximal to arch curve region (3006). Region(3008) has a length (L3) that may be, for example, from about 25 inchesto about 40 inches (e.g., from about 30 inches to about 40 inches, orfrom about 35 inches to about 38 inches, such as 36.828 inches). Aproximal portion (3010) of region (3008) has a length (L4) that may be,for example, from about 1 inch to about 4 inches (e.g., from about 2inches to about 3 inches, such as 2.473 inches). Additionally, andreferring still to FIG. 30B, arch curve region (3006) forms an archaving an arc diameter (AD4) that may be, for example, from about 3.5inches to about 5 inches (e.g., from about 3.5 inches to about 4.5inches, such as 4.045 inches), and defining a central angle (α8) thatmay be, for example, from about 60° to about 180° (e.g., from about 120°to about 180°, or from about 140° to about 160°, such as 153°). If afixture is used to form arch curve region (3006), the fixture may have acorresponding arch curve region comprising an arc with an arc diameterof, for example, 3.438 inches, and/or defining a central angle of, forexample, 180°.

Additionally, and referring now to FIG. 30C, diagnostic catheter (3000)comprises a tubular member (3012) having an outer diameter (OD2) and aninner diameter (ID2). In some variations, inner diameter (ID2) may befrom about 1.33 millimeters to about 3 millimeters. Alternatively oradditionally, outer diameter (OD2) may be from about 1.67 millimeters toabout 3.33 millimeters.

Referring now to FIG. 30D, arch curve region (3006) defines an archplane (3016), while transition curve region (3004) defines a transitionplane (3018). In certain variations, the angle (α9) between arch plane(3016) and transition plane (3018) may be from about 15° to about 35°(e.g., from about 20° to about 35°, such as 35°). If a fixture is usedto form transition curve region (3004) and arch curve region (3006), thefixture may have corresponding transition and arch curve regionsdefining transition and arch planes having an angle therebetween of, forexample, 35°.

As shown in FIG. 30E, transition curve region (3004) forms an arc havingan arc diameter (AD5) that may be, for example, from about 1 inch toabout 3 inches (e.g., from about 1 inch to about 2 inches, such as 1.176inches), and defining a central angle (α10) that may be, for example,from about 90° to about 270° (e.g., from about 180° to about 270°, fromabout 180° to about 250°, or from about 210° to about 250°, such as229.5°). If a fixture is used to form transition curve region (3004),the fixture may have a corresponding transition curve region comprisingan arc with an arc diameter of, for example, 1 inch, and/or defining acentral angle of, for example, 270°.

Additionally, and referring now to FIG. 30F, valve curve region (3002)defines a valve plane (3020). In certain variations, the angle (all)between transition plane (3018) and valve plane (3020) may be from about1000 to about 1250 (e.g., from about 105° to about 120°, such as 110°).If a fixture is used to form valve curve region (3002) and transitioncurve region (3004), the fixture may have corresponding valve andtransition curve regions defining valve and transition planes having anangle therebetween of, for example, 110°.

Finally, and referring now to FIG. 30G, valve curve region (3002) formsan arc having an arc diameter (AD6) that may be, for example, from about0.75 inch to about 1.5 inches (e.g., from about 0.75 inch to about 1inch, such as 0.88 inch), and defining a central angle (α12) that maybe, for example, from about 60° to about 80° (e.g., from about 70° toabout 80°, such as 76.5°). If a fixture is used to form valve curveregion (3002), the fixture may have a corresponding valve curve regioncomprising an arc with an arc diameter of, for example, 0.75 inch,and/or defining a central angle of, for example, 90°.

Example 2

FIG. 31A shows a computer illustration of a diagnostic catheter (3100).As shown there, diagnostic catheter (3100) comprises a valve curveregion (3102), a transition curve region (3104), and an arch curveregion (3106).

Referring now to FIG. 31B, diagnostic catheter (3100) also comprises aregion (3108) that is proximal to arch curve region (3106). Region(3108) has a length (L5) that may be, for example, from about 25 inchesto about 40 inches (e.g., from about 25 inches to about 35 inches, suchas 32.752 inches). A proximal portion (3110) of region (3108) has alength (L6) that may be, for example, from about 1 inch to about 4inches (e.g., from about 2 inches to about 3 inches, such as 2.473inches). Additionally, and referring still to FIG. 31B, arch curveregion (3106) forms an arc having an arc diameter (AD7) that may be, forexample, from about 3.5 inches to about 5 inches (e.g., from about 3.5inches to about 4.5 inches, such as 4.045 inches), and defining acentral angle (α13) that may be, for example, from about 60° to about180° (e.g., from about 120° to about 180°, or from about 140° to about160°, such as 153°). If a fixture is used to form arch curve region(3106), the fixture may have a corresponding arch curve regioncomprising an arc with an arc diameter of, for example, 3.438 inches,and/or defining a central angle of, for example, 180°.

Additionally, and referring now to FIG. 31C, diagnostic catheter (3100)comprises a tubular member (3112) having an outer diameter (OD3) and aninner diameter (ID3). In some variations, inner diameter (ID3) may befrom about 1.33 millimeters to about 3 millimeters. Alternatively oradditionally, outer diameter (OD3) may be from about 1.67 millimeters toabout 3.33 millimeters.

Referring now to FIG. 31D, arch curve region (3106) defines an archplane (3116), while transition curve region (3104) defines a transitionplane (3118). In certain variations, the angle (α14) between arch plane(3116) and transition plane (3118) may be from about 15° to about 35°(e.g., from about 20° to about 35°, such as 35°). If a fixture is usedto form transition curve region (3104) and arch curve region (3106), thefixture may have corresponding transition and arch curve regionsdefining transition and arch planes having an angle therebetween of, forexample, 35°.

As shown in FIG. 31E, transition curve region (3104) forms an arc havingan arc diameter (AD8) that may be, for example, from about 1 inch toabout 3 inches (e.g., from about 1 inch to about 2 inches, such as 1.176inches), and defining a central angle (α15) that may be, for example,from about 90° to about 270° (e.g., from about 180° to about 2700, fromabout 180° to about 250°, or from about 2100 to about 250°, such as229.5°). If a fixture is used to form transition curve region (3104),the fixture may have a corresponding transition curve region comprisingan arc with an arc diameter of, for example, 1 inch, and/or defining acentral angle of, for example, 270°.

Additionally, and referring now to FIG. 31F, valve curve region (3102)defines a valve plane (3120). In certain variations, the angle (α16)between transition plane (3118) and valve plane (3120) may be from about115° to about 150° (e.g., from about 125° to about 145°, such as 135°).If a fixture is used to form valve curve region (3102) and transitioncurve region (3104), the fixture may have corresponding valve andtransition curve regions defining valve and transition planes having anangle therebetween of, for example, 135°.

Finally, and referring now to FIG. 31G, valve curve region (3102) formsan arc having an arc diameter (AD9) that may be, for example, from about0.75 inch to about 1.5 inches (e.g., from about 0.75 inch to about 1inch, such as 0.88 inch), and defining a central angle (α17) that maybe, for example, from about 60° to about 800 (e.g., from about 70° toabout 80°, such as 76.5°). If a fixture is used to form valve curveregion (3102), the fixture may have a corresponding valve curve regioncomprising an arc with an arc diameter of, for example, 0.75 inch,and/or defining a central angle of, for example, 90°.

Example 3

FIG. 32A shows a computer illustration of a diagnostic catheter (3200).As shown there, diagnostic catheter (3200) comprises a valve curveregion (3202), a transition curve region (3204), and an arch curveregion (3206).

Referring now to FIG. 32B, diagnostic catheter (3200) also comprises aregion (3208) that is proximal to arch curve region (3206). Region(3208) has a length (L7) that may be, for example, from about 25 inchesto about 40 inches (e.g., from about 25 inches to about 35 inches, suchas 32.752 inches). A proximal portion (3210) of region (3208) has alength (L8) that may be, for example, from about 1 inch to about 4inches (e.g., from about 2 inches to about 3 inches, such as 2.473inches). Additionally, and referring still to FIG. 32B, arch curveregion (3206) forms an arc having an arc diameter (AD10) that may be,for example, from about 3.5 inches to about 5 inches (e.g., from about3.5 inches to about 4.5 inches, such as 4.045 inches), and defining acentral angle (α18) that may be, for example, from about 60° to about180° (e.g., from about 120° to about 1800, or from about 1400 to about160°, such as 153°). If a fixture is used to form arch curve region(3206), the fixture may have a corresponding arch curve regioncomprising an arc with an arc diameter of, for example, 3.438 inches,and/or defining a central angle of, for example, 180°.

Additionally, and referring now to FIG. 32C, diagnostic catheter (3200)comprises a tubular member (3212) having an outer diameter (OD4) and aninner diameter (ID4). In some variations, inner diameter (ID4) may befrom about 1.33 millimeters to about 3 millimeters. Alternatively oradditionally, outer diameter (OD4) may be from about 1.67 millimeters toabout 3.33 millimeters.

Referring now to FIG. 32D, arch curve region (3206) defines an archplane (3216), while transition curve region (3204) defines a transitionplane (3218). In certain variations, the angle (α19) between arch plane(3216) and transition plane (3218) may be from about 20° to about 45°(e.g., from about 35° to about 45°, such as 45°). If a fixture is usedto form transition curve region (3204) and arch curve region (3206), thefixture may have corresponding transition and arch curve regionsdefining transition and arch planes having an angle therebetween of, forexample, 45°.

As shown in FIG. 32E, transition curve region (3204) forms an arc havingan arc diameter (AD11) that may be, for example, from about 1 inch toabout 3 inches (e.g., from about 1 inch to about 2 inches, such as 1.176inches), and defining a central angle (α20) that may be, for example,from about 90° to about 270° (e.g., from about 180° to about 270°, fromabout 180° to about 250°, or from about 210° to about 2500, such as229.5°). If a fixture is used to form transition curve region (3204),the fixture may have a corresponding transition curve region comprisingan arc with an arc diameter of, for example, 1 inch, and/or defining acentral angle of, for example, 270°.

Additionally, and referring now to FIG. 32F, valve curve region (3202)defines a valve plane (3220). In certain variations, the angle (α21)between transition plane (3218) and valve plane (3220) may be from about100° to about 1250 (e.g., from about 105° to about 120°, such as 110°).If a fixture is used to form valve curve region (3202) and transitioncurve region (3204), the fixture may have corresponding valve andtransition curve regions defining valve and transition planes having anangle therebetween of, for example, 110°.

Finally, and referring now to FIG. 32G, valve curve region (3202) formsan arc having an arc diameter (AD12) that may be, for example, fromabout 0.75 inch to about 1.5 inches (e.g., from about 0.75 inch to about1 inch, such as 0.882 inch), and defining a central angle (α22) that maybe, for example, from about 60° to about 80° (e.g., from about 70° toabout 80°, such as 76.5°). If a fixture is used to form valve curveregion (3202), the fixture may have a corresponding valve curve regioncomprising an arc with an arc diameter of, for example, 0.75 inch,and/or defining a central angle of, for example, 900.

Example 4

FIG. 33A shows a computer illustration of a diagnostic catheter (3300).As shown there, diagnostic catheter (3300) comprises a valve curveregion (3302), a transition curve region (3304), and an arch curveregion (3306).

Referring now to FIG. 33B, diagnostic catheter (3300) also comprises aregion (3308) that is proximal to arch curve region (3306). Region(3308) has a length (L9) that may be, for example, from about 25 inchesto about 40 inches (e.g., from about 25 inches to about 35 inches, suchas 32.752 inches). A proximal portion (3310) of region (3308) has alength (L10) that may be, for example, from about 1 inch to about 4inches (e.g., from about 2 inches to about 3 inches, such as 2.473inches). Additionally, and referring still to FIG. 33B, arch curveregion (3306) forms an arc having an arc diameter (AD13) that may be,for example, from about 3.5 inches to about 5 inches (e.g., from about3.5 inches to about 4.5 inches, such as 4.045 inches), and defining acentral angle (α23) that may be, for example, from about 60° to about180° (e.g., from about 120° to about 180°, or from about 140° to about160°, such as 153°). If a fixture is used to form arch curve region(3306), the fixture may have a corresponding arch curve regioncomprising an arc with an arc diameter of, for example, 3.438 inches,and/or defining a central angle of, for example, 180°.

Additionally, and referring now to FIG. 33C, diagnostic catheter (3300)comprises a tubular member (3312) having an outer diameter (OD5) and aninner diameter (ID5). In some variations, inner diameter (ID5) may befrom about 1.33 millimeters to about 3 millimeters. Alternatively oradditionally, outer diameter (OD5) may be from about 1.67 millimeters toabout 3.33 millimeters.

Referring now to FIG. 33D, arch curve region (3306) defines an archplane (3316), while transition curve region (3304) defines a transitionplane (3318). In certain variations, the angle (α24) between arch plane(3316) and transition plane (3318) may be from about 20° to about 45°(e.g., from about 35° to about 45°, such as 45°). If a fixture is usedto form transition curve region (3304) and arch curve region (3306), thefixture may have corresponding transition and arch curve regionsdefining transition and arch planes having an angle therebetween of, forexample, 45°.

As shown in FIG. 33E, transition curve region (3304) forms an arc havingan arc diameter (AD14) that may be, for example, from about 1 inch toabout 3 inches (e.g., from about 1 inch to about 2 inches, such as 1.176inches), and defining a central angle (α25) that may be, for example,from about 90° to about 270° (e.g., from about 180° to about 2700, fromabout 180° to about 250°, or from about 2100 to about 250°, such as229.5°). If a fixture is used to form transition curve region (3304),the fixture may have a corresponding transition curve region comprisingan arc with an arc diameter of, for example, 1 inch, and/or defining acentral angle of, for example, 270°.

Additionally, and referring now to FIG. 33F, valve curve region (3302)defines a valve plane (3320). In certain variations, the angle (α26)between transition plane (3318) and valve plane (3320) may be from about115° to about 150° (e.g., from about 125° to about 145°, such as 135°).If a fixture is used to form valve curve region (3302) and transitioncurve region (3304), the fixture may have corresponding valve andtransition curve regions defining valve and transition planes having anangle therebetween of, for example, 135°.

Finally, and referring now to FIG. 33G, valve curve region (3302) formsan arc having an arc diameter (AD15) that may be, for example, fromabout 0.75 inch to about 1.5 inches (e.g., from about 0.75 inch to about1 inch, such as 0.882 inch), and defining a central angle (α27) that maybe, for example, from about 60° to about 80° (e.g., from about 700 toabout 80°, such as 76.5°). If a fixture is used to form valve curveregion (3302), the fixture may have a corresponding valve curve regioncomprising an arc with an arc diameter of, for example, 0.75 inch,and/or defining a central angle of, for example, 900.

Example 5

FIG. 34A shows a computer illustration of a diagnostic catheter (3400).As shown there, diagnostic catheter (3400) comprises a valve curveregion (3402), a transition curve region (3404), and an arch curveregion (3406).

Referring now to FIG. 34B, diagnostic catheter (3400) also comprises aregion (3408) that is proximal to arch curve region (3406). Region(3408) has a length (L11) that may be, for example, from about 25 inchesto about 40 inches (e.g., from about 25 inches to about 35 inches, suchas 32.752 inches). A proximal portion (3410) of region (3408) has alength (L12) that may be, for example, from about 1 inch to about 4inches (e.g., from about 2 inches to about 3 inches, such as 2.473inches). Additionally, and referring still to FIG. 34B, arch curveregion (3406) forms an arc having an arc diameter (AD16) that may be,for example, from about 3.5 inches to about 5 inches (e.g., from about3.5 inches to about 4.5 inches, such as 4.045 inches), and defining acentral angle (α28) that may be, for example, from about 60° to about180° (e.g., from about 120° to about 180°, or from about 140° to about160°, such as 153°). If a fixture is used to form arch curve region(3406), the fixture may have a corresponding arch curve regioncomprising an arc with an arc diameter of, for example, 3.438 inches,and/or defining a central angle of, for example, 180°.

Additionally, and referring now to FIG. 34C, diagnostic catheter (3400)comprises a tubular member (3412) having an outer diameter (OD6) and aninner diameter (ID6). In some variations, inner diameter (ID6) may befrom about 1.33 millimeters to about 3 millimeters. Alternatively oradditionally, outer diameter (OD6) may be from about 1.67 millimeters toabout 3.33 millimeters.

Referring now to FIG. 34D, arch curve region (3406) defines an archplane (3416), while transition curve region (3404) defines a transitionplane (3418). In certain variations, the angle (α29) between arch plane(3416) and transition plane (3418) may be from about 15° to about 35°(e.g., from about 20° to about 35°, such as 35°). If a fixture is usedto form transition curve region (3404) and arch curve region (3406), thefixture may have corresponding transition and arch curve regionsdefining transition and arch planes having an angle therebetween of, forexample, 35°.

As shown in FIG. 34E, transition curve region (3404) forms an arc havingan arc diameter (AD17) that may be, for example, from about 1 inch toabout 3 inches (e.g., from about 1 inch to about 2 inches, such as 1.176inches), and defining a central angle (α30) that may be, for example,from about 90° to about 270° (e.g., from about 180° to about 270°, fromabout 180° to about 250°, or from about 2100 to about 250°, such as229.5°). If a fixture is used to form transition curve region (3404),the fixture may have a corresponding transition curve region comprisingan arc with an arc diameter of, for example, 1 inch, and/or defining acentral angle of, for example, 270°.

Additionally, and referring now to FIG. 34F, valve curve region (3402)defines a valve plane (3420). In certain variations, the angle (α31)between transition plane (3418) and valve plane (3420) may be from about100° to about 125° (e.g., from about 105° to about 120°, such as 110°).If a fixture is used to form valve curve region (3402) and transitioncurve region (3404), the fixture may have corresponding valve andtransition curve regions defining valve and transition planes having anangle therebetween of, for example, 110°.

Finally, and referring now to FIG. 34G, valve curve region (3402) formsan arc having an arc diameter (AD18) that may be, for example, fromabout 0.75 inch to about 1.5 inches (e.g., from about 0.75 inch to about1 inch, such as 0.882 inch), and defining a central angle (α32) that maybe, for example, from about 75° to about 120° (e.g., from about 100° toabout 120°, such as 114.75°). If a fixture is used to form valve curveregion (3402), the fixture may have a corresponding valve curve regioncomprising an arc with an arc diameter of, for example, 0.75 inch,and/or defining a central angle of, for example, 135°.

Example 6

FIG. 35A shows a computer illustration of a diagnostic catheter (3500).As shown there, diagnostic catheter (3500) comprises a valve curveregion (3502), a transition curve region (3504), and an arch curveregion (3506).

Referring now to FIG. 35B, diagnostic catheter (3500) also comprises aregion (3508) that is proximal to arch curve region (3506). Region(3508) has a length (L13) that may be, for example, from about 25 inchesto about 40 inches (e.g., from about 25 inches to about 35 inches, suchas 32.752 inches). A proximal portion (3510) of region (3508) has alength (L14) that may be, for example, from about 1 inch to about 4inches (e.g., from about 2 inches to about 3 inches, such as 2.473inches). Additionally, and referring still to FIG. 35B, arch curveregion (3506) forms an arc having an arc diameter (AD19) that may be,for example, from about 3.5 inches to about 5 inches (e.g., from about3.5 inches to about 4.5 inches, such as 4.045 inches), and defining acentral angle (α33) that may be, for example, from about 60° to about180° (e.g., from about 120° to about 180°, or from about 140° to about160°, such as 153°). If a fixture is used to form arch curve region(3506), the fixture may have a corresponding arch curve regioncomprising an arc with an arc diameter of, for example, 3.438 inches,and/or defining a central angle of, for example, 180°.

Additionally, and referring now to FIG. 35C, diagnostic catheter (3500)comprises a tubular member (3512) having an outer diameter (OD7) and aninner diameter (ID7). In some variations, inner diameter (ID7) may befrom about 1.33 millimeters to about 3 millimeters. Alternatively oradditionally, outer diameter (OD7) may be from about 1.67 millimeters toabout 3.33 millimeters.

Referring now to FIG. 35D, arch curve region (3506) defines an archplane (3516), while transition curve region (3504) defines a transitionplane (3518). In certain variations, the angle (α34) between arch plane(3516) and transition plane (3518) may be from about 15° to about 35°(e.g., from about 20° to about 35°, such as 35°). If a fixture is usedto form transition curve region (3504) and arch curve region (3506), thefixture may have corresponding transition and arch curve regionsdefining transition and arch planes having an angle therebetween of, forexample, 35°.

As shown in FIG. 35E, transition curve region (3504) forms an arc havingan arc diameter (AD20) that may be, for example, from about 1 inch toabout 3 inches (e.g., from about 1 inch to about 2 inches, such as 1.176inches), and defining a central angle (α35) that may be, for example,from about 900 to about 2700 (e.g., from about 180° to about 270°, fromabout 180° to about 250°, or from about 210° to about 250°, such as229.5°). If a fixture is used to form transition curve region (3504),the fixture may have a corresponding transition curve region comprisingan arc with an arc diameter of, for example, 1 inch, and/or defining acentral angle of, for example, 270°.

Additionally, and referring now to FIG. 35F, valve curve region (3502)defines a valve plane (3520). In certain variations, the angle (α36)between transition plane (3518) and valve plane (3520) may be from about115° to about 150° (e.g., from about 125° to about 145°, such as 135°).If a fixture is used to form valve curve region (3502) and transitioncurve region (3504), the fixture may have corresponding valve andtransition curve regions defining valve and transition planes having anangle therebetween of, for example, 135°.

Finally, and referring now to FIG. 35G, valve curve region (3502) formsan arc having an arc diameter (AD21) that may be, for example, fromabout 0.75 inch to about 1.5 inches (e.g., from about 0.75 inch to about1 inch, such as 0.882 inch), and defining a central angle (α37) that maybe, for example, from about 75° to about 120° (e.g., from about 100° toabout 120°, such as 114.75°). If a fixture is used to form valve curveregion (3502), the fixture may have a corresponding valve curve regioncomprising an arc with an arc diameter of, for example, 0.75 inch,and/or defining a central angle of, for example, 135°.

Example 7

FIG. 36A shows a computer illustration of a diagnostic catheter (3600).As shown there, diagnostic catheter (3600) comprises a valve curveregion (3602), a transition curve region (3604), and an arch curveregion (3606).

Referring now to FIG. 36B, diagnostic catheter (3600) also comprises aregion (3608) that is proximal to arch curve region (3606). Region(3608) has a length (L15) that may be, for example, from about 25 inchesto about 40 inches (e.g., from about 25 inches to about 35 inches, suchas 32.752 inches). A proximal portion (3610) of region (3608) has alength (L16) that may be, for example, from about 1 inch to about 4inches (e.g., from about 2 inches to about 3 inches, such as 2.473inches). Additionally, and referring still to FIG. 36B, arch curveregion (3606) forms an arc having an arc diameter (AD22) that may be,for example, from about 3.5 inches to about 5 inches (e.g., from about3.5 inches to about 4.5 inches, such as 4.045 inches), and defining acentral angle (α38) that may be, for example, from about 60° to about180° (e.g., from about 120° to about 1800, or from about 140° to about160°, such as 153°). If a fixture is used to form arch curve region(3606), the fixture may have a corresponding arch curve regioncomprising an arc with an arc diameter of, for example, 3.438 inches,and/or defining a central angle of, for example, 180°.

Additionally, and referring now to FIG. 36C, diagnostic catheter (3600)comprises a tubular member (3612) having an outer diameter (OD8) and aninner diameter (ID8). In some variations, inner diameter (ID8) may befrom about 1.33 millimeters to about 3 millimeters. Alternatively oradditionally, outer diameter (OD8) may be from about 1.67 millimeters toabout 3.33 millimeters.

Referring now to FIG. 36D, arch curve region (3606) defines an archplane (3616), while transition curve region (3604) defines a transitionplane (3618). In certain variations, the angle (α39) between arch plane(3616) and transition plane (3618) may be from about 20° to about 45°(e.g., from about 35° to about 45°, such as 45°). If a fixture is usedto form transition curve region (3604) and arch curve region (3606), thefixture may have corresponding transition and arch curve regionsdefining transition and arch planes having an angle therebetween of, forexample, 45°.

As shown in FIG. 36E, transition curve region (3604) forms an arc havingan arc diameter (AD23) that may be, for example, from about 1 inch toabout 3 inches (e.g., from about 1 inch to about 2 inches, such as 1.176inches), and defining a central angle (α40) that may be, for example,from about 90° to about 270° (e.g., from about 180° to about 270°, fromabout 180° to about 250°, or from about 210° to about 250°, such as229.5°). If a fixture is used to form transition curve region (3604),the fixture may have a corresponding transition curve region comprisingan arc with an arc diameter of, for example, 1 inch, and/or defining acentral angle of, for example, 270°.

Additionally, and referring now to FIG. 36F, valve curve region (3602)defines a valve plane (3620). In certain variations, the angle (α41)between transition plane (3618) and valve plane (3620) may be from about100° to about 125° (e.g., from about 105° to about 120°, such as 110°).If a fixture is used to form valve curve region (3602) and transitioncurve region (3604), the fixture may have corresponding valve andtransition curve regions defining valve and transition planes having anangle therebetween of, for example, 110°.

Finally, and referring now to FIG. 36G, valve curve region (3602) formsan arc having an arc diameter (AD24) that may be, for example, fromabout 0.75 inch to about 1.5 inches (e.g., from about 0.75 inch to about1 inch, such as 0.882 inch), and defining a central angle (α42) that maybe, for example, from about 75° to about 120° (e.g., from about 100° toabout 120°, such as 114.75°). If a fixture is used to form valve curveregion (3602), the fixture may have a corresponding valve curve regioncomprising an arc with an arc diameter of, for example, 0.75 inch,and/or defining a central angle of, for example, 135°.

Example 8

FIG. 37A shows a computer illustration of a diagnostic catheter (3700).As shown there, diagnostic catheter (3700) comprises a valve curveregion (3702), a transition curve region (3704), and an arch curveregion (3706).

Referring now to FIG. 37B, diagnostic catheter (3700) also comprises aregion (3708) that is proximal to arch curve region (3706). Region(3708) has a length (L17) that may be, for example, from about 25 inchesto about 40 inches (e.g., from about 25 inches to about 35 inches, suchas 32.752 inches). A proximal portion (3710) of region (3708) has alength (L18) that may be, for example, from about 1 inch to about 4inches (e.g., from about 2 inches to about 3 inches, such as 2.473inches). Additionally, and referring still to FIG. 37B, arch curveregion (3706) forms an arc having an arc diameter (AD25) that may be,for example, from about 3.5 inches to about 5 inches (e.g., from about3.5 inches to about 4.5 inches, such as 4.045 inches), and defining acentral angle (α43) that may be, for example, from about 60° to about180° (e.g., from about 120° to about 180°, or from about 140° to about160°, such as 153°). If a fixture is used to form arch curve region(3706), the fixture may have a corresponding arch curve regioncomprising an arc with an arc diameter of, for example, 3.438 inches,and/or defining a central angle of, for example, 180°.

Additionally, and referring now to FIG. 37C, diagnostic catheter (3700)comprises a tubular member (3712) having an outer diameter (OD9) and aninner diameter (ID9). In some variations, inner diameter (ID9) may befrom about 1.33 millimeters to about 3 millimeters. Alternatively oradditionally, outer diameter (OD9) may be from about 1.67 millimeters toabout 3.33 millimeters.

Referring now to FIG. 37D, arch curve region (3706) defines an archplane (3716), while transition curve region (3704) defines a transitionplane (3718). In certain variations, the angle (α44) between arch plane(3716) and transition plane (3718) may be from about 20° to about 45°(e.g., from about 35° to about 45°, such as 45°). If a fixture is usedto form transition curve region (3704) and arch curve region (3706), thefixture may have corresponding transition and arch curve regionsdefining transition and arch planes having an angle therebetween of, forexample, 450°.

As shown in FIG. 37E, transition curve region (3704) forms an arc havingan arc diameter (AD26) that may be, for example, from about 1 inch toabout 3 inches (e.g., from about 1 inch to about 2 inches, such as 1.176inches), and defining a central angle (α45) that may be, for example,from about 90° to about 270° (e.g., from about 180° to about 2700, fromabout 180° to about 250°, or from about 2100 to about 250°, such as229.5°). If a fixture is used to form transition curve region (3704),the fixture may have a corresponding transition curve region comprisingan arc with an arc diameter of, for example, 1 inch, and/or defining acentral angle of, for example, 270°.

Additionally, and referring now to FIG. 37F, valve curve region (3702)defines a valve plane (3720). In certain variations, the angle (α46)between transition plane (3718) and valve plane (3720) may be from about115° to about 150° (e.g., from about 125° to about 145°, such as 135°).If a fixture is used to form valve curve region (3702) and transitioncurve region (3704), the fixture may have corresponding valve andtransition curve regions defining valve and transition planes having anangle therebetween of, for example, 135°.

Finally, and referring now to FIG. 37G, valve curve region (3702) formsan arc having an arc diameter (AD27) that may be, for example, fromabout 0.75 inch to about 1.5 inches (e.g., from about 0.75 inch to about1 inch, such as 0.882 inch), and defining a central angle (α47) that maybe, for example, from about 75° to about 120° (e.g., from about 100° toabout 120°, such as 114.75°). If a fixture is used to form valve curveregion (3702), the fixture may have a corresponding valve curve regioncomprising an arc with an arc diameter of, for example, 0.75 inch,and/or defining a central angle of, for example, 135°.

Example 9

A study is conducted to provide three-dimensional support fordevelopment of catheter shapes. The study aims to define a cathetershape that achieves desired positioning of the catheter in thesubannular groove of a heart from an anterior approach, with appropriatebracing points against the greater curvature of the aortic arch andwithin the ascending aorta contralateral to the entrance of thesubannular groove.

Eight subjects of varying age (50±16 years) and sex (5 male, 3 female)are analyzed with SimVascular, a specialized imaging software that maybe used to build custom geometric models from medical image data. Byvisualizing the medical image data directly, the user may be able toisolate specific parts of the anatomy and build-up shapes inthree-dimensional space based on these images. For this study,cardiac-gated CT image data (i.e., data based on the optimizedacquisition of images during moments in time when the heart isquiescent) is used. An image volume representing one-tenth of thecardiac cycle is analyzed for each patient, and an idealized path of acatheter is drawn in three-dimensional space.

Several visualization options are available in SimVascular, includingpoint cloud and isosurface. The point cloud visualization renders theimage data with varying densities of white dots, based on the imageintensity at that location. The user can choose the range of intensitiesto visualize, providing flexibility in the level of detail. The pointcloud visualization may be appropriate, for example, for checking theoverall position of the catheter (e.g., because the point cloudvisualization can provide some transparency). Another visualizationmodality is the isosurface, which allows the user to create a solidsurface with detailed features based on the image intensity. Theisosurface visualization may be appropriate, for example, for checkingthe positioning of the catheter along the mitral annulus (e.g., becausethe isosurface visualization may allow for a more detailed view of theedges of the anatomy).

The path generated in SimVascular is extracted into SolidWorks as thebasis for the catheter model. For each patient, two catheter models arecreated. The first model strictly follows the path extracted fromSimVascular, while the second model is an idealized catheter created byconfining the catheter to three distinct planes. The first plane(MVPlane) represents the segment of the catheter which lies solely belowthe mitral annulus, extrapolating an extension of the catheter path fromcommissure to commissure. The second plane (TransitionPlane) representsthe segment of the catheter spanning from the mitral valve to theascending aorta. Finally, the third plane (ArchPlane) represents thelength of the catheter resting along the aortic arch. All planes andcurves are created as a best-fit approximation by the user. In somevariations, a catheter model may be created using a least-squaresapproximation or may be manually created (e.g., by tracing an optimizedpath with a computer mouse).

Several measurements are taken on the models of alleight subjects. TheMVPlane-TransitionPlane measurement represents the angle between theidealized mitral valve plane and the idealized transition plane, theTransitionPlane-ArchPlane measurement represents the angle between theidealized transition plane and the idealized arch plane, and theMVPlane-ArchPlane measurement represents the angle between the idealizedmitral valve plane and the idealized arch plane, according to theanatomy of the particular subject.

The length of the curve drawn onto each of the three planes is alsomeasured (MVCurve, TransitionCurve, ArchCurve). In addition, the radiusof curvature for the three curves (MVRadius, TransitionRadius,ArchRadius) is reported. In some cases, several curves are used toconstruct an arch. In Tables 1-3 below, only the first curve (directlyadjacent to the transition curve) is measured.

TABLE 1 Measured Angle (Degrees) Between the Three Planes. MVPlane-TransitionPlane- MVPlane- TransitionPlane ArchPlane ArchPlane Subject1 00 0 Subject2 0 0 0 Subject3 0 67 67 Subject4 10 0 10 Subject5 35 27 62Subject6 49 69 20 Subject7 12 24 12 Subject8 1 61 60

TABLE 2 Measured Lengths (mm) of the Three Segments of an IdealizedCatheter. MVCurve TransitionCurve ArchCurve Subject1 42 21 65 Subject260 82 110 Subject3 46 20 89 Subject4 53 51 38 Subject5 64 54 51 Subject650 45 50 Subject7 57 45 86 Subject8 62 42 86

TABLE 3 Measured Radius of Curvature (mm) of the Three Segments of anIdealized Catheter. MVRadius TransitionRadius ArchRadius Subject1 13 3639 Subject2 22 31 35 Subject3 17 22 43 Subject4 16 32 56 Subject5 20 2428 Subject6 17 23 34 Subject7 19 35 38 Subject8 21 27 42

In Table 1 above, the angle between the transition plane and the mitralvalve plane ranges from 0° to 49°, with the mean angle at 13°. Thisimplies that this dimension should be varied in the final catheterdesign to accommodate various patient anatomies, with more incrementalchanges closer to the lower range of the measurements. Additionally, theangle between the transition plane and the arch plane ranges from 0° to69°, with the mean angle at 310. Any variations in this dimension may beequally incremented over the range. Finally, the angle between themitral valve plane and the arch plane ranges from 00 to 67°, with themean angle at 29°.

The length of the catheter in contact with the mitral valve annulus hasa range from 42 millimeters to 64 millimeters, with the mean at 54millimeters. The length of the transition curve varies from 20millimeters to 82 millimeters, with the mean at 45 millimeters. Finally,the length of the arch curve has a broad range from 38 millimeters to110 millimeters, with the mean at 72 millimeters.

The radius of curvature for the mitral valve ranges from 13 millimetersto 22 millimeters, with the average at 18 millimeters. This range maynot require variation from patient to patient. The transition curve hasa radius of curvature ranging from 22 millimeters to 36 millimeters,with the mean at 29 millimeters. Because of the important role thetransition curve plays in bracing the catheter, it may be preferable tovary this parameter to accommodate patient variability. Finally, thearch radius of curvature varies from 28 millimeters to 56 millimeters,with the mean at 39 millimeters. This dimension likely may be heldconstant across all patient groups.

Example 10

A catheter suitable for probing the subannular groove of a mitral valveand the anatomy surrounding the subannular groove using ultrasound isconstructed. The catheter includes the following segments.

First, the catheter includes a distal window formed of 70D PEBAX®polymer. The window, which is cylindrical, has a length of about 0.5centimeter to about 1 centimeter, and a wall thickness of about 0.007inch. The catheter also includes an ultrasonic transducer disposedwithin the distal window.

Additionally, the catheter includes a flexible distal segment that isproximal to the distal window. The flexible distal segment has abi-lumen construction, and includes an inner layer formed ofhigh-density polyethylene (HDPE), an intermediate layer formed of 35DPEBAX® polymer, and an outer jacket formed of 40D PEBAX® polymerincluding 20% by weight barium sulfate. The smaller lumen has an innerdiameter of about 0.01 inch to about 0.012 inch, and the larger lumenhas an inner diameter of about 0.045 inch to about 0.056 inch. Theflexible distal segment has an outer diameter of about 0.07 inch, and alength of about 2 inches to 4 inches.

The catheter further includes a proximal segment that is stiffer thanthe distal segment. The proximal segment has a bi-lumen construction,and comprises 70D PEBAX® polymer and stainless steel braid. The smallerlumen of the proximal segment has an inner diameter of about 0.012 inchto about 0.016 inch, and the larger lumen has an inner diameter of about0.05 inch to about 0.06 inch. The proximal segment has an outer diameterof about 0.089 inch, and a length of about 60 inches to 70 inches.

Example 11

The ease of inserting a catheter to a body location may be influenced bya number of catheter characteristics. While a catheter made from stiffermaterials may exhibit improved user responsiveness relatingtorqueability and/or pushability over longer insertion distances,stiffer catheter materials may also affect the catheter'smaneuverability through tight anatomical bends. In some cases, cathetermaneuverability may be improved by using a steering mechanism toposition the catheter tip in the desired orientation or direction. FIG.38 illustrates one example of a steerable catheter segment, comprising atubular catheter body (3804) with one or more conduits (3806) and a pulllumen (3808) containing a pull member (3810). Pull member (3810) may beattached distally to catheter body (3804) such that, when pulledproximally, pull member (3810) will asymmetrically compress catheterbody (3804) to cause bending, as shown in FIG. 39A. While a steeringmechanism (3812) may facilitate the bending of stiffer cathetermaterials, such materials may sometimes cause creases (3814) or otherdiscontinuities in catheter body (3804) when bent, as illustrated inFIG. 39A. In some examples, creases (3814) may impair the ability topass instruments (3816) or components through conduit (3806), as isapparent in FIG. 39B.

In some instances, a catheter may be configured with a higher durometersegment that may provide torqueability and/or pushability, along with alower durometer segment that may provide flexibility and/orcompressibility, which may reduce the kinking and/or creasing that mayaffect the conduct. In some further variations, the materials withdifferent durometers may comprise two or more partially tubular segmentsof material with a generally semi-circular or other arcuatecross-sectional shape. The two segments may be joined along theirlongitudinal edges or otherwise oriented to form the tubular structure.A catheter configured with multiple durometer materials along itscircumference or perimeter may facilitate flexion or compression of thecatheter in at least one direction while also providing sufficientcolumn strength along the same longitudinal segment of the catheter.

In one example, shown in FIG. 40A, a steerable catheter (4000) with oneor more deformation regions (4002) is provided. Referring to FIG. 40B,deformation region (4002) may comprise a segment of the catheter body(4004) having a first layer segment (4006) and a second layer segment(4008) with a longitudinal interface (4010) therebetween. First layersegment (4006) and second layer segment (4008) comprise differentphysical characteristics such that first layer segment (4006) is able tocompress or stretch when flexed. In some variations, first layer segment(4006) comprises a material having a lower durometer than the materialof second layer segment (4008). In examples where deformation region(4002) is formed by two layer segments, two longitudinal interfaces areformed where the two lateral borders of each layer segment form alongitudinal interface with the complementary lateral border of theother layer segment. Longitudinal interface (4010) may have a linear orsimple curve configuration, which may be oriented similar to thelongitudinal axis of catheter body (4004). In other variations describedbelow, the deformation region may alternatively comprise non-curvilinearinterfaces. Also, although first layer segment (4006) and second layersegment (4008) in this specific example have generally semi-circularconfigurations, longitudinal interfaces (4010) have generally 180°opposite locations. In other variations, however, deformation regioninterfaces may be angularly closer together, and/or a deformation regionmay comprise three or more interfaces.

In some variations, deformation region (4002) may correspond to at leasta portion of (e.g., the entirety of) the transition curve region of theother exemplary catheters described herein. In other variations, thedeformation region may correspond to the other portions of the exemplarycatheters, including but not limited to the valve curve regions, archcurve regions, or combinations of any of the valve curve, transitioncurve and arch curve regions. Deformation region (4002) may beconfigured to bend from about 180° to about 300, about 180° to about 45°in some variations, and about 180° to about 90° in other examples. Incertain variations, deformation region (4002) may be configured to bendin two or more directions and/or two or more planes from its straight orbase configurations. The range of bending in two or more directions orplanes need not be symmetrical with respect to a linear configuration orother base configuration, which may not be linear. Catheter body (4004)may be formed from any of a variety of materials, as described above. Insome further variations, first layer segment (4006) and second layersegment (4008) may comprise different materials or the same general typeof material but with different durometers. For example, first layersegment (4006) may comprise PEBAX® 35D polymer and second layer segment(4008) may comprise PEBAX® 72D polymer. In other variations, thedurometer of the material may range from about 5D to about 72D, in somevariations about 35D to about 72D, and in other variations about 35D toabout 55D, or about 55D to about 72D. Catheter body (4004) may compriseone or more layers, and sometimes two or more layers. Although FIG. 40Bdepicts first layer segment (4006) and second layer segment (4008) asforming the outermost layer of deformation region (4002), in otherexamples, these layer segments (4006) and (4008) may be covered by oneor more other layers or reinforcing structures. Catheter body (4004)need not comprise the same number of layers along its entire length. Instill other examples, the deformation region may comprise a tubular bodythat is asymmetrically reinforced with respect to different angularregions, such that the tubular body functionally has a region ofincreased stiffness and a region of increased compressibility orflexibility.

Referring back to FIG. 40A, catheter body (4004) may further comprise aproximal shaft (4012) and a distal shaft (4014) with respect todeformation region (4002). Proximal shaft (4012) may comprise a tubularconfiguration with at least one inner lumen (not shown) that may beoptionally lined with a coating. Proximal shaft (4012) may have agenerally linear configuration, but in other variations, proximal shaft(4012) may have a non-linear configuration, including angled and curvedsections or combinations thereof, such as the arch curve region (4018).Distal shaft (4014) may also have a linear or curved configuration, suchas valve curve region (4020) depicted in FIGS. 40B and 40C. In somevariations, proximal shaft (4012) may comprise one or more reinforcementstructures (4022), such as tubular or arcuate braiding or interweaving,circular loops, helical structures, or longitudinal supports. Thereinforcement structure may comprise one or more metallic and/ornon-metallic materials. In one example, proximal shaft (4012) maycomprise an outer layer of PEBAX® 72D polymer, and reinforcementstructure (4022) may comprise a tubular stainless steel wire braid,which in turn may have an inner coating of PTFE. Distal shaft (4014) maycomprise the same material(s) as proximal shaft (4012) or deformationregion (4002), or may comprise one or more different materials. In theexample of FIG. 40A, distal shaft (4014) comprises a material having adurometer between the durometer of first and second segments (4006) and(4008), but in other examples, the durometer may be generally equal to,less than or greater than first and second segments (4006) and (4008),respectively. Distal shaft (4014) may also comprise an atraumatic tip(4024), which may comprise a material having a lower durometer than therest of distal shaft (4014), or may be tapered or otherwise shaped to bemore flexible or deformable. Distal shaft (4014) may comprise a linearor non-linear configuration, and may be oriented in the same or adifferent plane with respect to the deformation region (4002) and/orproximal shaft (4012), as shown in FIG. 40D.

In some variations, deformation region (4002) may have an angularorientation of about 0°, about 15°, about 30°, about 45°, about 60°,about 75°, about 90°, about 105°, about 120°, about 135°, about 150°,about 165°, about 180°, about 195°, about 210°, about 225°, about 240°,about 255°, about 270°, about 285°, about 300°, about 315°, about 330°,or about 345°. The bending plane of deformation region (4002), however,need not be the same plane as its curved configuration and may have anangular orientation from about 0° to about 359° to the plane of itscurved configuration. In some variations, the bending plane ofdeformation region has an angular orientation of about 0°, about 15°,about 30°, about 45°, about 60°, about 75°, about 90°, about 105°, about120°, about 135°, about 150°, about 165°, about 180°, about 195°, about210°, about 225*, about 240°, about 255°, about 270°, about 285°, about300°, about 315°, about 330°, or about 345° with respect to the plane ofits curved configuration.

In certain variations, deformation region (4002) may have a longitudinallength of about 0.75 inch to about 10 inches, some variations about 1inch to about 4 inches or more, and in other variations about 1.5 inchesto about 2 inches in length. In some variations, deformation region(4002) may have similar inner and outer diameters as described forcatheter body (4004), but in other variations of deformation region(4002), the inner diameter and/or outer diameter may be smaller orlarger.

Although several variations depicted and described herein have a singleinner lumen, in other variations, two or more lumens may be providedalong part or all of the catheter body. Variations with multiple lumensneed not have lumens with the same diameter, shape or cross-sectionalarea. Furthermore, any one lumen need not have the same diameter, shapeor cross-sectional area along its entire length. Thus, some lumens maycomprise a circular shape, but in other variations, the lumens may beoval, square, rectangular or any other shape.

Referring to FIG. 40B, proximal shaft (4012) may further comprise a pulllumen (4026) and pull member (4028) within the wall of proximal shaft(4012). Pull lumen (4026) and/or pull member (4028) may also be coatedwith a reduced friction coating, such as PTFE. In further variations,pull lumen (4026) may be reinforced with a material such as polyimide.Pull member (4028) may comprise any of a variety of materials, includingbut not limited to stainless steel, nylon, polyimide, and the like.

In variations comprising a single deformation region and/or steeringmechanism, pull lumen (4026) and/or pull member (4028) may terminatewithin deformation region (4002) or distal shaft (4014). To facilitatethe exertion of force in distal shaft (4014) of catheter body (4004),pull member (4028) may comprise a distal pull structure (4030). Pullmember (4028) may be welded or twisted around distal pull structure(4030) or may be contiguous with distal pull structure (4030). In thevariation illustrated in FIG. 40B, distal pull structure (4030) maycomprise a ring-like structure embedded in distal shaft (4014). Inalternate variations, distal pull structure (4030) may comprise ahelical winding of pull member (4028) or some other wire-basedconfiguration. Pull member (4028) may comprise any of a variety ofmaterials and structures sufficient to transmit longitudinal forcesalong a length of catheter body (4004). Pull member (4028) and distalpull structure (4030) may be metallic, non-metallic or a combinationthereof, comprising one or more materials including but not limited tostainless steel, Nitinol, nylon and/or other polymeric materials. Insome variations, pull member (4028) may be coated, for example, tofacilitate sliding in pull lumen (4026). In certain variations, suchcoatings may include polytetrafluoroethylene (PTFE).

In some variations, pull member (4028) may comprise a structure and amaterial whereby pull member (4028) can exert force on catheter body(4004) only when pulled. In such variations, catheter body (4004) mayhave a preconfigured shape such that when the force acting on pullmember (4028) is released, catheter body (4004) is biased to return toits preconfigured shape. In other variations, pull member (4028) has asufficient stiffness such that pull member (4028) may also be pushed tofacilitate bending of catheter body (4004) in a direction generallydifferent or opposite from the bending that occurs when pull member(4028) is pulled. In other variations, distal pull structure (4030) maybe located within deformation region (4002).

Tensioning of pull member (4028) may be controlled by any of a varietyof steering mechanisms, including but not limited a pull tab, lever,slider, or knob mechanism, for example. FIG. 40D depicts the proximalend (4031) of steerable catheter (4000), comprising a rotatable knob(4032), a guide hub interface (4034), a hemostatic valve (4036) and astopcock (4038). Knob (4032) is configured to adjust the tension in pullmember (4028) by knob rotation, but in other variations, tensionadjustment may occur by pulling the knob. Referring to FIG. 40E, pullmember (4028) is attached to a hypotube (4040) by crimping, welding,adhesives or the like. Hypotube (4040) may be attached to a keystructure (4042) which forms a complementary interfit with knob (4032)to axially displace pull member (4028) while permitting relativerotational movement between knob (4032) and key structure (4042). Keystructure (4042) may also be axially secured to knob (4032) using ascrew (4044) or other attachment structure which permits relativerotational movement. In other variations, the knob may be configured totransmit rotational movement to the pull member.

An inner sleeve (4046) with an outer threaded surface (4048) is attachedto the base (4050) of the steering assembly. Outer threaded surface(4048) interfaces with the inner threaded surface (4052) of knob (4032).In some variations, to permit axial movement while restrictingrotational movement of pull member (4028), hypotube (4040) or keystructure (4042) may be configured with a non-circular shape and/or oneor more side protrusions which may resist rotational movement along aninner lumen (4054) of inner sleeve (4046). For example, FIG. 40E depictsinner lumen (4054) comprising an elongate groove (5056) whichaccommodates axial movement of set screws (5058) attached to andprotruding from key structure (4042) while restricting rotationaldisplacement of screws (5058).

To reduce the risk of blood or fluid leakage from catheter (4000) duringa procedure, proximal end (4031) may comprise hemostatic valve or seal(4036) through which instruments may be inserted or withdrawn. Thehemostatic seal may comprise any of a variety of configurations known inthe art. In some examples, the hemostatic seal may comprise one or moreslits on a septum or sealing member which forms one or more seal flaps.Upon insertion of an instrument or device through the sealing member,the seal flaps may deform or deflect to permit passage of the devicewhile exerting force around a perimeter of the device to substantiallyresist passage of fluid or gas through the sealing member. Referring toFIGS. 41A-41C, in some examples, the sealing member (4100) has a sealopening (4102) comprising at least one non-linear slit (4104 a)-(4104 d)with respect to the seal face (4106) or a transverse plane of the sealaxis (4108). In the depicted example, the sealing opening (4102)comprises four arcuate or spiral-shaped slits (4104 a)-(4104 d) arrangedabout the seal axis (4108). Each of the slits (4104 a)-(4104 d) has thesame relative shape and size as the other slits (4104 a)-(4104 d), andthe slits are uniformly spaced around the axis (4108). However, in otherexamples, a different number of slits may be provided, one or more slitsmay have a different size and/or shape, the slits may be non-uniformlyspaced or non-symmetrically arranged, and/or the slits may intersect ata location different from the center of the seal face (4106). In FIG.42, for example, the sealing member (4130) comprises a plurality ofmulti-angled slits (4132 a)-(4132 d). Referring back to FIG. 40D,hemostatic valve (4036) and stopcock (4038) may be detached from guidehub (4034) to permit direct insertion of instruments into catheter(4000), or to attach other configurations of hemostatic seals, valves,connectors, sensors and the like.

Referring back to FIGS. 41A-41C, slits (4104 a)-(4104 d) may have agenerally orthogonal orientation through seal face (4106), or may beangled or skewed. In some examples, slits (4104 a)-(4104 d) may begenerally angled with respect to seal face (4106) in the range of about5° to about 85°, in certain configurations about 100 to about 60°, andin other configurations about 20° to about 45°. Seal face (4106) orsealing member (4100) may comprise any of a variety of elastic orflexible materials, including any of a variety of silicones such asNuSil Med-4035, Med-4820, and/or MED50-5338, may have a durometer in therange of about 20 to about 80 or about 15 to about 60 (e.g., about 20 toabout 40). The thickness (4110) of seal face (4106) may be in the rangeof about 0.01 inch to about 0.1 inch, in some examples about 0.02 inchto about 0.05 inch, and in other examples about 0.025 inch to about 0.03inch. As illustrated in FIG. 41C, seal face (4106) may be raised oroffset from body (4112) of sealing member (4100). The raised distance(4114) of raised seal face (4106) may be in the range of about 0.01 inchto about 0.2 inch, in some configurations about 0.02 inch to about 0.1inch and in other configurations about 0.04 inch to about 0.06 inch.

Body (4112) of sealing member (4100) comprises a lumen (4116) incommunication with sealing opening (4102). Lumen (4116) may have auniform or non-uniform diameter, cross-sectional area and/orcross-sectional shape. Lumens with non-uniform diameters may tapertoward or away from sealing opening (4102), and the taper may be linearor non-linear. In some examples, lumen (4116) may have an averagediameter (4118) in the range of about 0.05 inch to about 0.5 inch ormore, in some configurations about 0.1 inch to about 0.3 inch, and inother configurations about 0.15 inch to about 0.2 inch. Lumen (4116) mayhave a length (4120) anywhere in the range of about 0.1 inch to about 1inch or more, in some configurations about 0.2 inch to about 0.5 inch,and in other configurations about 0.25 inch to about 0.4 inch. Body(4112) may have any of a variety of shapes, including cylindrical,frustoconical, box-like or other shapes, and may be coupled to the guidetunnel by a frame or housing.

Example 12

Although the example depicted in FIG. 40A comprises a steerable catheter(4000) with a deformation region (4002) with a longitudinal linearinterface (4010) between the first layer segment (4006) and the secondlayer segment (4008), in other examples, a catheter may be configureddifferently. As an example, a catheter may have a non-linear interfacebetween the sections of material, such as a zig-zag or sinusoidalinterface. In some variations, a non-linear interface may permitcontrolled deformation of the lower durometer material between portionsof higher durometer material. This deformation may include stretchingand/or compression. In certain variations, the deformation region mayreduce the buckling of higher durometer material that may interfere withinsertion or withdrawal of catheters or instruments from the lumen ofthe guide catheter.

In the variation depicted in FIG. 43, the steerable catheter (4300) hasa deformation region (4302) with a longitudinal interface (4304) that isoriented along a similar axis as the longitudinal axis of catheter body(4306) but with a zig-zag configuration. The zig-zag configuration oflongitudinal interface (4304) comprises alternating protruding sectionsof first layer segment (4308) and second layer segment (4310). In FIGS.44A-44C, these alternating protruding sections, shown in this particularvariation as triangular sections (4312) and (4314), have side lengths(4316) and (4318) which meet to form an angle (4320) between twoadjacent sides (4316) and (4318). In FIG. 44C, when deformation region(4302) is straightened from its configuration in FIG. 44B, triangularsections (4314) of first layer segment (4308) are stretched or relievedof compression as angle (4320) is increased by the angular separation oftriangular sections (4314) of second layer segment (4310). In contrast,as depicted in FIG. 44A, when deformation region (4302) is acutely bentrelative to FIG. 44B, triangular sections (4312) of first layer segment(4308) are compressed as angle (4320) is decreased by the angularreduction of triangular sections (4314) of second layer segment (4310).In some variations, the zig-zag pattern may reduce the incidence ordegree of pinching or creasing of any conduits in deformation region(4302) by controlling compression of the lower durometer material infirst layer segment (4308) with the protruding sections (4314) of thehigher durometer material in second layer segment (4310). Further, incertain variations, the zig-zag pattern may provide a more evendistribution of the forces along the full length of deformation region(4302), compared to simple linear or simple curved interfaces. In somevariations, second layer segment may be contiguous with either theproximal and/or distal shaft of the steerable catheter.

As depicted in FIGS. 45A-45C, other variations of catheter regions withmultiple durometers include interfaces having a reciprocating patternincluding but not limited to a square wave pattern (4330), a scallopedpattern (4340), and a sinusoidal pattern (4350), respectively. As shownin FIG. 45D, the reciprocating pattern (4360) need not have symmetricsubsegments. In this variation, for example, the leading edge (4362) hasa different length and angle from the trailing edge (4364).

As depicted in FIGS. 46A-46C, interfaces need not comprise the samerepeating pattern along their entire length. For example, in thevariation depicted in FIG. 46A, an interface (4370) comprises a linearportion (4372) followed by a zig-zag portion (4374) and another linearportion (4376). In another variation depicted in FIG. 46B, an interface(4380) comprises the same pattern but with sections of low amplitude(4382) and (4386) and high amplitude (4384). In still another variationshown in FIG. 46C, interface (4390) comprises a pattern of similaramplitude but contains portions with relatively shorter and longerrepeating lengths (4392) and (4394), respectively. These features may bemixed and matched to achieve the desired structural features in adeformation region of a catheter.

As mentioned previously, the variation depicted in FIG. 43 comprises adeformation region (4302) with two similarly sized semi-circularsegments (4308) and (4310), and two interfaces (4304) about 180° apartwith respect to catheter body (4306). In other variations, however,segments may have different sizes and/or shapes. In FIG. 47A, forexample, the deformation region (4700) comprises a first segment (4702)with a reduced width at one or more ends and a second segment (4704)having a complementary larger size, resulting in interfaces (4706) and(4708) forming a narrower angle in one section (FIG. 47B) as compared toanother section (FIG. 47C). In other variations, and as depicted inFIGS. 48A-48C, the deformation region (4800) may comprise more than twosegments (4802)-(4806) and more than two interfaces (4808)-(4814).

In some variations, such as the example depicted in FIG. 43, deformationregion (4302) comprises a single steering mechanism, but in othervariations, multiple pull lumens with multiple pull members may beprovided. In FIG. 49A, for example, the steerable catheter (4900)comprises a deformation region (4902) with three layer segments(4904)-(4908) arranged to facilitate the bending of the deformationregion in opposite directions. As shown in FIG. 49B, two steeringmechanisms (4910) and (4912) may be provided to facilitate bending inopposite directions. In certain variations, two or more steeringmechanisms may be located at least about 15° (e.g., about 15°, about30°, about 45°, about 60°, about 75°, about 90°, about 105°, about 120°,about 135°, about 150°, about 165°, about 180°, about 195°, about 210°,about 225°, about 240°, about 255°, about 270°, about 285°, about 300°,about 315°, about 330°, or about 345°) with respect to the plane of thecurved configuration. In some variations, multiple steering mechanismswith different distal longitudinal terminations along the length ofcatheter body (4904) may be provided, to facilitate along differentlengths of bending. The longitudinal separation may be about 1centimeter to about 50 centimeters or more, sometimes about 5centimeters to about 20 centimeters, and other times about 5 centimetersto about 10 centimeters apart.

Example 13

A 14 Fr guide catheter (i.e., having an outer diameter of 4.67millimeters) including six different sections is formed.

In order of the most distal section to the most proximal section, theguide catheter includes: a first distal-most section having a length of5 millimeters and comprising PEBAX® 35D polymer, a second section havinga length of 11 millimeters or 19 millimeters (depending on theconfiguration of any curve regions in the catheter) and comprisingPEBAX® 63D polymer, a third section having a length of 2 millimeters andcomprising PEBAX® 55D polymer, a fourth section having a length of 2millimeters and comprising PEBAX® 72D polymer, a fifth section having alength of 1.5 to 2 centimeters and including a segment comprising PEBAX®72D polymer and a segment comprising PEBAX® 35D polymer, and a sixthsection having a length of about 95 centimeters and comprising PEBAX®72D polymer.

The catheter also includes a deflectable element comprising a stainlesssteel wire, one end of which is attached to a stainless steel ring. Thestainless steel ring, in turn, is attached to the catheter shaft. Duringuse, an operator may pull on the deflectable element to deflect thefifth section of the catheter.

The guide catheter is made by separately forming each of theabove-described six sections, and then fusing the sections togetherusing a hot box to apply heat to reflow the material. During the fusionprocess, fluorinated ethylene propylene (FEP) heat-shrink tubing (e.g.,FEP HS 1.3:1 AWG Heat Shrink, from ZEUS, Orangeburg, S.C.) is providedaround the six catheter sections to help maintain the overall outerdiameter of the catheter as it is formed, and to help the differentsections fuse together.

In this and other examples described herein, the non-linearconfiguration of the distal section of the guide catheter may act as analignment structure or otherwise facilitate the registration oralignment of other catheters (or instruments) passed over or insertedinto the guide catheter. These alignable or registerable catheters maycomprise a complementary non-linear alignment configuration and thenon-linear configurations of the guide catheter and/or the alignablecatheter may comprise at least one non-linear semi-rigid region having adurometer of at least 50, 55, 63 or 72 on a Shore D scale. The two (ormore) catheters may exhibit a reduced stress when in alignment (e.g.,longitudinally and/or rotationally) and an increased stress when out ofalignment. In some variations, the frictional resistance between the twocatheters is sufficiently low such that the stress forces in thecatheters may urge the catheters to slide into a reduced stressconfiguration, for example automatically aligning or registering the twocatheters when they are close to alignment or registration. In somevariations, increased tactile resistance from sliding the two cathetersout of their reduced stress configuration may provide additionalguidance during alignment, as well as visual markers located on one orboth catheters, which may be viewed on fluoroscopy or other imagingmodalities.

The complementary configuration of the alignable catheter may be thesame as or similar to any of the catheter configurations describedherein, but configured with a smaller or larger diameter for insertioninto or passage over the guide catheter, respectively. In some examples,the complementary configuration may comprise a shorter or greater lengththan the non-linear configuration of the guide catheter. Thecomplementary configuration may also comprise a material (or materials)that may be the same as, or different from, the corresponding section(s)of the guide catheter. The durometer(s) of the complementaryconfiguration may be the same as, lower than, or higher than thecorresponding areas on the guide catheter. For example, use of aflexible material in the complementary configuration of the alignablecatheter that corresponds to the sections of the guide catheter havingtighter bends further facilitate the desired relative positioning of thetwo catheters.

In some variations, the non-linear configuration of the guide cathetermay be located at the distalmost portion of the guide catheter, orproximal to the distal end. The non-linear configuration may be locatednext to the catheter regions to be aligned, and may be located anywherealong the length of a catheter. In some specific examples, thenon-linear configuration is distal to the deflectable portion of theguide catheter and proximal to the distal end. The location of thecomplementary non-linear configuration of the alignable catheter mayvary depending upon the relative extension distance of the alignablecatheter when the two catheters are aligned. In some examples, theextension distance of the alignable catheter may be in the range ofabout 1 cm to about 20 cm or more, sometimes about 2 cm to about 15 cm,and other times about 5 cm to about 10 cm, and still other times about 6cm to about 8 cm. In one specific example, the aligning cathetercomprises a multi-opening guide tunnel catheter where the complementarynon-linear alignment configuration is located proximal to the multipleopenings of the guide tunnel.

While the methods, devices, and kits have been described in some detailhere by way of illustration and example, such illustration and exampleis for purposes of clarity of understanding only. It will be readilyapparent to those of ordinary skill in the art in light of the teachingsherein that certain changes and modifications may be made theretowithout departing from the spirit and scope of the appended claims. Asan example, in some variations, a catheter may be custom-made for aparticular patient. For example, computed tomography (CT) scans of thepatient's anatomy may be used to design a catheter (e.g., a diagnosticcatheter, a visualization catheter, a guide catheter, and/or an anchordeployment catheter) appropriate for the patient (e.g., using one ormore computer imaging methods, such as described above). As anotherexample, in certain variations a catheter may include one or moresensors that may be used to indicate when the catheter is adjacent to atissue wall, such as a heart wall. In this way, the sensor or sensorsmay be used to help position the catheter at a target site. As anadditional example, in some variations, a heart chord may be manipulated(e.g., severed) by application of heat to a region of the heart chord(e.g., using a catheter comprising a heating member). As a furtherexample, in certain variations, a heart chord may be severed using oneor more rotating cutters and/or rotating grinders. As another example,in some variations, an operator may manipulate one or more heart chordsduring a surgical method. For example, an operator may see one or moreinterfering heart chords during a surgical method, and may sever thechord(s).

1-25. (canceled) 26: A method for positioning a guidewire, the methodcomprising: advancing a catheter through an aortic valve into asubvalvular space of a mitral valve of a left ventricle, wherein thecatheter comprises a longitudinal lumen and a curved distal portion;advancing a guidewire through the longitudinal lumen; positioning theguidewire by advancing the catheter and the guidewire around thesubvalvular space behind chordae tendineae of the left ventricle suchthat a distal portion of the guidewire is directed around at least aportion of the circumference of the left ventricle and back toward theaortic valve. 27: The method of claim 26, wherein the distal portion ofthe guidewire crosses the aortic valve. 28: The method of claim 26,wherein the guidewire at least partially encircles the subvalvularspace. 29: The method of claim 26, wherein the guidewire is opposedagainst endocardium in the subvalvular space. 30: The method of claim26, wherein positioning the guidewire includes positioning the catheteraround the subvalvular space behind the chordae tendineae. 31: Themethod of claim 26, wherein positioning the guidewire comprises torquingthe catheter along a wall of the ventricle and advancing the guidewirearound the subvalvular space behind the chordae tendineae. 32: Themethod of claim 31, wherein positioning the guidewire further comprisesadvancing the guidewire from the catheter along the subvalvular space.33: The method of claim 26, further comprising withdrawing the guidewirefrom the catheter and advancing a second guidewire into the catheter.34: The method of 26, wherein the guidewire does not interfere with thechordae tendineae. 35: The method of 26, further comprising acquiringfluoroscopic images of the catheter and the guidewire. 36: The method ofclaim 26, wherein positioning the guidewire comprises advancing theguidewire such that a distal portion of the guidewire is directed in anantegrade direction toward the aortic valve. 37: The method of claim 26,further comprising acquiring echocardiographic images of the catheter.38: The method of 29, wherein the guidewire is advanced in thesubvalvular space between the chordae tendineae and a ventricular wall.39: The method of 31, further comprising manipulating the catheter toposition the distal portion of the catheter against the ventricle wallbehind the chordae tendinae.